AITA for wanting to warn my ex’s pregnant wife that he suggested I should raise their child?

I (28F) recently moved into a new neighborhood, excited for a fresh start. I wanted some peace, a new apartment, and the chance to meet new people without the drama of my past hanging over me. What I didn’t expect was discovering that my high school ex, let’s call him J (30M), also lives in the same area.

J and I dated for about two years as teens. At the time, I thought it was serious, but we broke up in high school and went our separate ways. I moved on a long time ago, and honestly, I had no lingering feelings. I never thought I’d see him again, let alone in my own neighborhood.

A few weeks ago, he suddenly appeared at my door. He said he was “just in the area” and wanted to catch up. I was caught off guard, but I let him talk for a few minutes before politely reminding him that I’m in a new place and not interested in reconnecting romantically. I assumed that would be the end of it.

Here’s the thing — J is now married, and his wife is pregnant with their first child. On the surface, they appear to be a happy, stable couple, stepping into the next stage of their life together. And I truly want them both to be happy.

But privately… he keeps “running into me” or showing up at my apartment under the guise of coincidence. When he does, he unloads his marital frustrations on me. Hours-long monologues about how his wife doesn’t understand him, how he feels trapped, and how he wonders “what could have been” with us.

I’ve been very clear: I’m not interested, I’m dating someone new (we’ve been keeping it lowkey but it’s serious), and I do not want to be dragged into his personal drama. I thought he would eventually respect my boundaries, but last week, he crossed a line that made my stomach drop.

He said: “Sometimes I think about leaving her and going for full custody. You’d be a much better mom for this baby than she could ever be.”

I froze. That’s not just a flirtation or venting; that’s invasive, delusional, and deeply disrespectful to his wife. I told him immediately that it was completely inappropriate and ended the conversation.

After he left, I couldn’t stop thinking about it. The words replayed in my mind, and I felt a mix of anger, disgust, and anxiety. I can’t believe he thinks it’s acceptable to say that, let alone to me. He’s married, she’s pregnant, and instead of supporting his wife, he’s fantasizing about me being the mother of his child.

Now I’m stuck. On one hand, I feel like I should tell his wife. She’s pregnant, she deserves honesty, and she certainly doesn’t need this stress hanging over her. But on the other hand, is it really my place? I wasn’t involved in their relationship and I don’t want to inject myself into marital drama unnecessarily.

I also thought about contacting his parents. Maybe they could intervene in a way that’s less confrontational than telling his wife directly. But that feels indirect and complicated. I don’t want to create gossip, and I also don’t want him to manipulate the story later, making me look like the instigator.

Blocking him seems like the safest route. I’ve already made it clear I’m not interested, and if he respects that boundary, the problem goes away. But then, I feel morally conflicted. Am I complicit if I stay silent while he says things like that to me? Is keeping this secret a form of passive harm, since he’s potentially jeopardizing his wife’s emotional wellbeing?

I keep running scenarios through my head:

• If I tell his wife, she might be grateful, but the fallout could be catastrophic. J could deny it, claim I’m lying, or paint me as manipulative. The drama could be enormous.
• If I block him and say nothing, I’m protecting myself, but she might eventually find out some other way. Would she resent me for not warning her?

I also feel anxious thinking about how he might escalate. He’s already showing signs of obsession: appearing “by chance,” talking endlessly about his regrets, crossing boundaries. If he knows I told his wife, I’m concerned about retaliation — passive-aggressive behavior, attempts to contact me, or even harassment.

I’ve had to remind myself: my responsibility is to protect myself, my mental health, and my relationship. I cannot control his marriage, his choices, or his fantasies. But I can control my response and how I set boundaries.

I’ve consulted with friends and a therapist about the situation. Everyone agrees: he crossed a huge line, and his behavior is inappropriate and manipulative. The therapist emphasized that my moral obligation is complicated. Telling his wife could be protective, but it could also create chaos and unintended consequences.

I’ve thought about documenting everything — keeping a record of his visits, the conversations, and the boundary violations — just in case I need it later for legal or safety reasons. That gives me some control over the situation, even if I don’t immediately act on it.

This has been stressful. I feel anxious leaving my apartment, worried he might show up again. I feel conflicted about my new relationship; I don’t want this baggage to spill over. And I feel guilty for even thinking about telling his wife, because I don’t want to be seen as someone who stirs drama.

Yet, I feel morally uneasy keeping this to myself. It’s one thing to hear someone vent about marital frustrations; it’s another entirely to hear them say you’d be a better parent than their spouse and suggest leaving them for you. That’s beyond venting — it’s actively disrespectful and emotionally manipulative.

From a psychological perspective, this is a clear case of boundary violation. J is projecting fantasies and dissatisfaction onto me, using guilt and manipulation to test limits. It’s not my responsibility to fix his marriage, but it’s reasonable for me to protect myself and set firm boundaries.

The moral tension comes from empathy for his wife. I can understand wanting to protect someone from emotional harm, especially someone pregnant. But I also have to balance that against potential fallout and my own mental health.

The anxiety I’m feeling is natural — this is a high-conflict, unpredictable situation. The stress of dealing with someone who is manipulative, persistent, and crossing boundaries can be significant, especially when tied to moral questions about disclosure and honesty.

I don’t want to cause unnecessary drama, but I also don’t want to be complicit in a situation that could hurt someone. I’m weighing my options: block him entirely and protect my peace, tell his wife and risk chaos, or document and monitor while maintaining distance.

So… AITA if I tell his wife what he said? Or WIBTA if I just block him and never say a word? I feel torn between protecting myself and wanting to prevent harm to his wife, but I honestly don’t know which choice is the “right” one.