I completely understand your situation and it's so frustrating!!!!
One of my best friends started going out with this guy and completely changed! Suddenly, she's too tired to go out withher girlfriends, or doesn't have any money. But, she'll meet up with her boyfriend to go dancing when he gets off work at 2am! I haven't seen her for two weeks, and haven't really hung out with her for about a month. She didn't return my calls or e-mails until they broke up last week. All of a sudden, she wanted to go out and e-mailed me. I was busy, so I told her I couldn't go. I haven't heard from her since. Now I hear from another friend that she got back together with him. I'll probably never see her again....