I, personally, am not eligible to give you a reply. I, myself, am one of those girls who also refuses to see a therapist or anything like that, which also gives my boyfriend a lot of headaches

I'm not sure if I was raped (violated, yes; raped, unsure. my brother didn't go all the way so I don't really know), but to offer my opinion, it seems that she (like me), is afraid of opening up this sort of shameful things to some stranger. Having someone talk about you about rts and things like that is akin to admitting that she had been raped. Which I don't think she wants to. Compared to talking with someone she doesn't know, she'd rather confide in you, someone whom she loves and trusts. I know it's problematic, but I'm just telling you how she probably feels. About your breaking relationship, I don't know anything about that, but from what I see she feels like she can really confide in you. She trusts you. I'm not saying that she doesn't need therapy, just that it's hard to open up to people and admit hat something like that happened to you. I, too, think I need therapy, but the thought of facing a stranger that knows your deepest most shameful secret is a very scary process.
Perhaps try to persuade her slowly, maybe following her into the room too. It'll give her a small sense of security that you are there to support her, and that she isn't alone. Just a suggestion only, I'm not sure it'll work but try not to let your relationship break down, okay. She's at her weakest and most vulnerable moment and desperately needs you.