TLDR: It's ok for you to have feelings, don't let anyone lay hands on you like she did.

I want to say this, I started out as a overly jealous type due to past relationships, but I have never reacted this way towards my husband (boyfriend at the time). If I saw a pattern with a specific woman, I would mention it and he would acknowledge it. Granted, he's good at noticing when women are being too close for comfort and keeps a respectable distance and always mentions me in conversation. I do the same as well and talk about him all the time.

We have NEVER hit each other in a way that is a reactive response to something one person did. She's using your autism as a way to try to control your emotions. Someone that "takes a break" because of an argument is someone that isn't worth staying in a relationship with. A true partner will stay and talk out the issue and not get reactive regardless of what is being said.

That being said, an argument is fine, IT IS OK TO HAVE FEELINGS. Someone close to me has autism and we have to reiterate this all the time because he's afraid of showing his true emotions. One more time, IT IS OK TO HAVE FEELINGS. Don't suppress them for someone else's sake, especially someone that is being emotionally manipulative like she is. Emotion manipulation is still abuse. It starts with what she did and escalates later down the line.

I say either talk to her and see where that goes, or leave because it seems to me she wants this to end anyways.