Have you ever been in the situation where your best buddy turned around and started dating your most recent ex girlfriend? How did you handle the situation? Were you cool about it or were you pissed off as soon as you found out? About a month ago my best friend I had grown up with for 19+ years turned around and decided to start dating my latest ex girlfriend. When I found out I was upset, pissed enough at him I ended the friendship for only a few weeks. I learned quick that ending a relationship with a good friend over a girlfriend is stupid. Now my buddy and I are pretty good friends, been able to build a friend relationship with my ex as well.