I'm kind of relieved for your sake. No. it is not possible for someone to change that drastically in one year. And she has just proved that by demanding you commit this soon in her "recovery." The truth is that she knew she couldn't keep up the act too much longer. I do believe she wants to change, but she is abusive and she hasn't changed. Her ultimatum to you was abusive. How do you think she will treat your kids?

Stop feeling sorry for her. Yes, her behavior is ansolutely a product of what she grew up with, and I don't doubt she received very hard treatment herself. But your future kids shouldn't have to pay for that, and they will, if you marry her. You're a nice guy. Go find yourself a nice girl. She's too damaged. She's not a nice person. It doesn't really matter that it may not be her fault.