How to filter messages from your ex without their cooperation (or an app)

When a relationship ends but contact cannot, many people reach a point where they want to control what reaches them, without turning it into another negotiation. The trouble is that most filtering tools depend on the other person: both of you have to download the same app, create accounts and send everything through it.

If your ex will not cooperate, and high-conflict people rarely do, the tool simply does not work.

The other common advice, a second phone number or a spare email address, hides your real details but does nothing about the content. You still open every message and absorb every insult. You have moved the problem, not solved it.

This guide explains a third option: a one-sided filter that you set up on your own, that needs nothing from the other person, and that changes what actually reaches you. It covers how it works, what the other person sees, and why it is a fair and legitimate way to manage contact you cannot avoid.

Why one-sided filtering helps

Asking a hostile ex to agree to a new way of communicating is often a fight in itself. A one-sided setup removes that step. You do not need their permission, their participation or a conversation about it. Here is why that matters:

• Safety and coercion. Where there is controlling behaviour, threatening messages or a history of harassment, a request to change how you communicate can become a new point of leverage or provocation. A setup that needs nothing from them avoids handing them that opening.
• Avoiding escalation. Even in lower-conflict situations, asking an ex to download an app and agree to new rules can start a new argument. Giving them an ordinary email address or number to use does not.
• Mental health and boundaries. Receiving co-parenting logistics without also absorbing hostile language or manipulation protects your wellbeing. You do not need anyone’s agreement to look after yourself.
• Professional or legal advice. Some lawyers and family dispute resolution practitioners recommend that clients put a buffer between themselves and a high-conflict ex, particularly when communications may later be relevant in proceedings.

Why apps and second numbers fall short

Most of the tools people try first fall into two groups, and each has a catch.

Apps that both people must use

Many co-parenting and messaging tools only work if both people sign up and send through the same app. That is fine when both people are willing. When one person is not, the tool cannot do anything for you, and you are left asking the most difficult person in your life for a favour. That includes OurFamilyWizard; see what OurFamilyWizard costs and the alternatives.

A separate email address or second number

Giving your ex a new email address or a second phone number solves part of the privacy problem, because they do not have your real details. It does not solve the filtering problem. Every message they send still lands in full. You still open your phone to find hostile language, manipulation or distressing content. The address is separate, but there is no buffer between what they send and what you read.

The problem with phone-level blocking

The instinct many people have is to simply block the other person’s number or email address. If the relationship is entirely over and contact genuinely needs to stop, blocking is appropriate. But in co-parenting situations, property settlements, or anywhere a legal process is still running, blocking creates specific problems:

• You lose the record. Messages you never receive cannot be kept. If the other party later claims they sent reasonable communications and you ignored them, you have no record to disprove it.
• They find other ways in. A blocked number does not stop someone from using a new number, a family member’s phone, email or social media. Each new avenue requires a new block, and each one is a gap in your record.
• It could be raised as non-cooperation. In family court or mediation, the other person might describe a pattern of blocking as obstructing communication about children or shared obligations. A one-sided filter receives everything; you simply control what reaches you directly.

How a one-sided filter works

A one-sided filter gives you a contact address, and on some plans a phone number, that you share with your ex instead of your real details. Only you sign up. They email or text that address the way they would any contact, using whatever phone or email app they already have. They install nothing, need no account and set up nothing. Our guide on how FenceChat works covers set-up.

On your side, every incoming message passes through a filter before it reaches you. That filter:

• Reads the message for hostile, threatening or abusive content
• Removes content designed to harm or manipulate
• Passes through genuine factual content: logistics about children, times, appointments and requests that need a response
• Keeps the full original with a timestamp, whatever was removed from the version you read

The calm, factual version arrives in your inbox and your Dashboard, and you decide when to read it. A threatening message no longer ambushes you on your lock screen.

Your real details stay private

Because everything routes through FenceChat, the other person never sees your real email address or mobile number. When you reply, your reply goes back through FenceChat too, so your real details stay private in both directions. On SMS, only the people you add as contacts can reach your FenceChat number, so unknown numbers, strangers and spam do not get through.

The psychological benefit of a buffer

There is a meaningful difference between knowing that hostile messages exist and having them arrive directly in front of you. When a message lands on your phone at 10pm with abusive language buried inside a question about a school pickup, the abusive language still lands on you, even if the question is genuine.

A one-sided filter removes that dynamic. What you receive is the factual content: the question about the school pickup, without the surrounding hostility. The original message is kept in your Archive, so you have a complete record, but your day-to-day experience of communication is limited to what actually requires your attention.

For many people, this is the difference between being able to co-parent sustainably and reaching a point of crisis. The buffer is not about avoiding responsibility for communication. It is about being able to engage with that communication without being repeatedly harmed by it.

A complete record, kept for you

Some people keep evidence with a screenshots habit or a folder of forwarded emails. That takes effort, and it is easy to miss things. FenceChat does it automatically: both versions of every message, the original and the filtered one, are stored with a timestamp. If a situation escalates and you need to show a pattern to a lawyer or the police, the record is already there, and on the Legal plan you can export it as a timestamped PDF formatted for your lawyer.

It is not just for co-parenting

High-conflict co-parenting is a common reason people look for a one-sided filter, but the same problem shows up in many places: a business client who has turned hostile, a former employee sending threatening messages, a family member who uses every message to pick a fight, a neighbour in a long-running dispute, a customer who crosses the line. Anywhere you need to stay reachable but cannot keep absorbing the hostility, a one-sided filter fits, and the other person still never needs to install anything.

Is a one-sided filter fair to the other person?

This is worth answering directly, because many people ask themselves the question before taking this step.

A one-sided filter is not a trick, and it is not hidden. The first time someone messages your FenceChat address or number, they receive a one-time notice that messages are processed by AI and stored by FenceChat. Where telling the sender could put you at risk, for example where there is a history of family violence, you can switch that notice off. That safety exception exists to protect you, not to mislead anyone. For the legal side, see is it legal to filter messages.

The other person also keeps everything they need to communicate with you:

• They can still reach you. Messages are filtered, not blocked. Genuine logistics, questions and requests come through.
• They still receive your replies. You reply as normal, and your reply reaches them through FenceChat.
• The original is kept. Nothing they send is deleted. The full original is stored in your Archive with a timestamp, so there is an accurate record of exactly what was said.

What they do not see is what was removed from the version you read, or your real email address and number. That follows the same principle as an answering service, a receptionist or a legal practice manager: many people in professional settings have difficult contact routed through a third party before they see it. You are still providing a contact channel. You are simply controlling how it delivers content to you, and that is a reasonable boundary to set.

Practical steps: switching over

Once you have set up your FenceChat address, the transition is straightforward:

1. Give your ex your new contact details. You can do this in writing: “Please use this number and email for all future communications.” You do not need to negotiate or ask for their agreement. It is simply your contact address for this purpose.
2. Check your parenting orders or written agreements. If a parenting order (in the US, a custody order) or binding agreement specifies contact by a particular number or email, a lawyer can tell you whether you need to do anything formal before you change it.
3. Stop using your real details for this contact. Consistency matters. If you keep replying from your real number now and then, the filter cannot protect you. All outgoing messages in this relationship should go through your FenceChat address or number.
4. Let relevant support people know. If you have a lawyer, family dispute resolution practitioner or support worker involved, let them know you have changed the contact method. They may want to note it on their records.
5. Check your Archive periodically, not constantly. One of the main benefits of a filter is that you are not receiving hostility in real time. Set a time to review your Dashboard rather than treating it like a live inbox. This gives you the information you need without the constant exposure.