What would you like your life to be like?
I'm going to talk about myself for a bit, but it's to show you're not alone. (The reason I warn is because I've had at least one person get confused by that before.) I know that being raped and used can strip a person of who they are. I'm still not sure how it does that. I just know that when I was, I lost all sense of who I am. I know how confusing it is to be told by people who don't like me very much who they think I am with absolute conviction that what they're saying is fact. I know that trying to act normal so, hopefully, people won't hurt me anymore is exhausting and ends up taking up all the room in my head so there's no room for me in there. It's just full of these other people. I know that being taught that I'm insane and out of control makes me even more out of control and makes me doubt myself and my perceptions.
Does that sound familiar?
This is just my advice and what has worked for me. I'm going to try and leave out the stuff you've probably heard before though like therapy and DBT and stuff.
This is going to take a long time. Pick a small step and deal with that first. Figuring out who you are is a life long thing since people change over time. Personally, I love this, but I'm a brain fanboy.
One of the most profound realizations for me was realizing that I am very strong. Like you, I didn't expect to survive, but I did. I thought I couldn't handle it, but I was the whole time. Nothing had managed to take me down permanently and I made a decision that nothing ever would.
As for figuring out who you are, I really think that first you need to mentally separate yourself from other people and how they treat you. You are not how people treat you. You are your own person. I'd also suggest deciding not to try to force yourself to fit into puzzle.
There are tricks for helping to figure out who you are like figuring out what you value, what you like, etc. Personality tests can sometimes help. Mostly, it requires a lot of introspection.
I hope I made sense.