You do deserve happiness, but you are one half of the equation. The other half is her.
Most of the time when I hear about relationship problems it is clear that the one (or both) having a problem is not willing to do anything. In your case, the situation seems to be different: from what you wrote she seems very interested in getting better.
There are two possibilities from here: one is that she goes for some counseling and therapy and stays persistent until she changes (yes, they say we shouldn't expect our partners to change but I dno't believe in that). Or she may neglect her own development (which happens in 99% of cases), and then slowly starts putting the burden of the situation on you in various creative ways.
A 2a possibility is that she does change, but replaces one problem with another. So maybe she seemingly overcomes her memories and problems from the terrible rape experience, but never quite plays those emotions out and only learns to bury them even more deeply. This then causes many more problems, years later when the burden becomes unbearable...
The second scenario would probably play out after some sort of an improvement. So be careful, and observe well. Just because you want to have a good relationship with her, you are more likely to see things which are not there, but which you want to happen.
My tone may sound calculated, but that is only because I am very well aware that worst abusers on the planet are those who were abused themselves. And as much as we all feel for those victims of abuse, we have to be careful not to become the victims ourselves. And abused people who didn't overcome their negative experience always find ways to abuse others, even if it is not physical. Interestingly enough, abused people will blame the very person who is closest to them and who is trying to help and may at some point become revengful and take that out on that same person, knowing full well that that person is not the original abuser.