<human>: Can you summarize the given text in a few sentences?

My boyfriend and I have been together for 10 months, 2 weeks ago he opened up to me about this previous relationship of his and how his girlfriend was abusive. She would hit him, be very controlling and not let him to have female friends, and even pressure him into sexual stuff when he was hesitant/nervous about doing. Because of this stuff he has been hesitant about being intimate with me and even opening up to me emotionally or getting close with me, and I think it has given him some deep issues. I told him I want to confront her about this, and he said he doesn't want me to. I don't want to go against him wishes, but I'm really angry about it and want to do something so he knows that I care for him. I think that maybe deep down he does want me to, because I think why would he have told me if he didn't want me to do anything?

What do you think I should do? I want her to realize how fucked up she is and I want to cause her pain that she caused to my boyfriend. I've never been in a fight before and am not a particularly large or strong girl lol, so I am nervous about actually fighting her. Do you think maybe I should just confront her verbally? Or just message her on Instagram? I don't want to sound like I'm over reacting but please mind I'm from Chile and even though I live in the US now I am not exactly familiarized with this customs and how people act in these sort of situations, so maybe it's a bit of a cultural difference. But where I grew up if a girl did that to your boyfriend it would be normal to be that angry at her that you would fight her.
<bot>: My boyfriend opened up to me about abusive ex-girlfriend, I want to confront her but he said he doesnt want me to.