Most Helpful Girl
First of all, let me say, that what you are doing is AWESOME!!! The fact that you put all this time into overcoming your behavior and going to counseling is something rare among people who are abusive. It shows you realize what you did was wrong and actually do want to change! I believe in you!
Just give her some time. Eventually she maybe will stay overnight. Just do everything you possibly can to show her you are changing and want to change. Keep going to therapy and work hard to be a good boyfriend! Your actions will speak louder than your words and, overtime, she'll regain her trust of you!