Sounds like alot of good is happening in your life despite the pit falls you are going through. Obviously they really like you at your new job to offer you a perminent postion there. That has to be a really big boost to your self asteem along with working out and dropping weight, good for you!
Not seeing your D everyday has to be hard, hopefully she understands and you have a great time with her this weekend.
As for the stbx, I would not go into his house nor give him the opportunity to be alone with you. The less interaction with him the better for you. Too much chitt like that on tv and I see no reason to put yourself in that situation.
Take care and smile your doing what is best and right for you and that is all that is important at the moment. Let the demons fend for themselves its too damn cold way up north for them anyways so don't let them in.