I agree, it isn't too late to change. You're not any worse than anyone else, you're a human with both good and bad qualities. You did the right thing by reaching out to people on here, and I'm very glad you didn't 'carry out' the things you had intended to do.
What happened to you can never go away, it was a horrible thing that is inexcusable. But it was not your fault. In fact, it is very common for people who are the victims of sexual abuse to try and express themselves through sexual acts. It helps them heal or feel connected to someone who isn't going to hurt them. So yes, you should refrain from doing this---but it isn't like you're some freak or a horrible person for feeling like this. You had lots of stuff happen to you, and you deserve to have a life of your own.
If you do have the urge to self harm in anyway, I would take the advice of the others on here. Call a crisis hotline--even 911. Your life has value, and many people--maybe even yourself one day--will completely appreciate that and be so grateful that you took the steps to try and get better.