I don't regret letting any ex-boyfriends slip away. The relationships ended, and we moved on.
There was one guy, though, that was interested in me directly prior to starting my relationship with the most recent ex. He was smart and funny and talented... he was interning at a hospital and played piano on the weekends. We got along fabulously, and had a lot of fun together. But...N was making it clear that he wanted to be exclusive, so I told E he'd be better off just walking away. He did.
I'm happy in my current relationship (
), but I sometimes think if I'd spent three years with E instead of N, I wouldn't have the self esteem issues that I deal with now. Ah, well. Hindsight's 20/20, as they say.