How do u support my girlfriend

I've been with my girlfriend for 6 months, a few months before we got together she was raped and beaten. She had to stop taking her antidepressants, antipsychotics when we found out she was pregnant 4 weeks ago, she's 10 weeks now. We fight a lot, I have anger problems, but we get through it. She says when we figt bad all them thoughts come back. Last night she through a plate at me. The next second she was crying her eyes out, rocking back and forward pulling her hair repeating I can't do this, I'm sorry. She says she's scared of snapping and hurting someone, she thinks because that stuff happened to her, she'll do it to someone else. I don't know how to support her and make her feel happy again.