What has helped me when I struggle with getting stuck in the past is remembering that who that person is today is because of the experiences in the past. Maybe if they hadn't done those things, they wouldn't have become the person I love and cherish today. It's going to take work, and you're going to have to really want to change the way you think about her past (which is a lot harder than it sounds...), but it is definitely worth it if you truly love her and value your relationship with her.