personally, sounds to me like you guys have a lot you need to discuss if you do want to get back together with her. The number of arguments that occured and both of your reactions to what happened over the Christmas holiday seem to show me that... but that's just an outsiders perspective looking in.
What do you want? We can't tell you that - you need to decide for yourself. Are you happier with her or without her? What makes it easier for you to sleep at night?
Who knows, if you are able to talk to her and get things sorted out you may find that gives you peace of mind and you will be better able to make the right decision for yourself - to be with her or to be without her.
