Woman's SIL demands she break up with 'scary' BF and move in with her; she refuses. AITA? UPDATED

"AITA for refusing to move in with my brother and his pregnant wife?"

I (21f) have a boyfriend (22m) of 3 years who have ASPD. My SIL who is 5 months pregnant is scared of him and wanted me to end my relationship. After her pestering me for days and me trying to reassure her that I have a support system and my boyfriend will be completely cut off from her child, she still wouldn't stop texting me everyday to breakup.

Me and my boyfriend decided to 'fake breakup' until the baby is born. Today I was running an errand for my brother and his wife, SIL ask me if I'm still seeing my boyfriend to which I answered no. She told me I make the right decision and said that she can finally have a peaceful sleep.

She keep talking about how her stress level have been going up because of my relationship and she's glad she won't have to raise a kid in the presence of my boyfriend. This is where I might be the AH— SIL ask me if I will move in with them, I answer with a simple "no."

When she said she hasn't stated the reason for her request and asked me to listen her, I told her "I don't really care about your reason, I won't move in with you" and walked out of the house.

She texted me, saying it's unfair and cruel of me to be upset at her for trying to do what's best for everyone, she wanted me to stay with them so she can keep an eye on me and that I put her under lots of stress which is bad for pregnancy. I feel like the AH but also thinks she's pushing me too much.

This is what top commenters had to say about the situation:

PaleontologistOk3120 said:

NTA. Your SIL is trying to manipulate you into being her live in help. First by making sure you were single. Next by getting you to move in. Don't lie to her anymore, and block her number. Tell your you won't be letting his wife harass you anymore.

PeopleWatchOlympian said:

NTA- sounds like she’s trying to strip you of a support system so you can help with her kid. But there is likely more to this story…why do they know about your boyfriend’s diagnosis? Has he ever acted towards them in a way that might be concerning? Where they would have cause for concern for their child?

DJ_Too_Supreme said:

NTA. Why is your SIL so fixated on your relationship and what is ASPD? Also, the option of no is always an option. However, you shouldn’t have to hide your relationship because your SIL don’t like it.

And No-Train8518 said:

The Internet says ASPD is antisocial personality disorder. I am wondering if he said or did something very inappropriate with her for to act like this. If not, her reaction seems quite strange. You need to talk to your brother alone. Personally I think you’re in for a lifetime of heartache living with someone with this disorder. It’s not their fault they were born with it, but they are not capable of real change.

After speaking with her brother and SIL, she posted this update:

My brother have a talk with my SIL and she have called me to apologize for her behavior, I came clean about the fake breakup, she says it's wrong of her to assume the worst in my bf, my brother ask her what would she do if their child was unfortunate enough to have the same diagnosis.

That changed her perspective (her words) but she have her concern still and think it's best for my bf to keep his distance until further notice. And she will be speaking to her doctor about her anxiety and stress, she also offered to apologize to my boyfriend but my boyfriend says he doesn't care about some pretty words and tell her to manage her own health(both mental and physical).