That's quite a situation you are in. I have a question for you. Why are you still pondering your next move when this person has treated you with such disrespect/distain? You sound like you put alot of energy into this relationship while she goes about her business and and seems to give little thought to how her actions affect you.
Your words tell me you have a loving family...go on back and start over. Relationships are tough enough without one of the parties being destructive. It sounds like you have a lot going for you. I'm sure there is someone out there who will appreciate the effort you put into a relationship. Don't waste your effort on anyone who isn't willing to put the same effort in.