My ex and I have been occasionally sleeping together once, sometimes twice a month, since we broke up about six months ago. In the last month, I met another girl and things are going well. I had a missed call from my ex the other night for a booty call, I haven't spoken to her for a while. Just wondering how I should go about telling her I'm seeing someone. Is it a douche move to call her to tell her? I don't want to rub it in or anything, I just want to let her know cause I feel like I owe it to her to tell her and I don't want to keep her thinking that I'm still down for what we were doing.

Thoughts?