I've got to agree with this guy, use it as motivation to better yourself. I was in a similar situation as you (wildvs2). I realised I spent way to much time and effort on a girl, and since then just like you I've started hitting the gym a lot, getting heaps better grades at uni and am moving up very quickly at work. However I did the stupid thing when she begged for me back and said yes, obviously didn't end well. But acex throw yourself into something else to get your mind off it, I converted my car to a manual to keep my mind off it. Don't let it stop you from things in your own life, you've said its cost you your diploma if it was me I would try and get that back on track as others have said.