I guess this calls for a bit more context to illustrate why this relationship was particularly unhealthy. First of all, it was long distance - she lives over 500 miles away - so it was primarily virtual. Second, she was already involved in a LTR relationship. It wasn't a very happy relationship anymore, which left her open to getting involved with me, but in retrospect, I should have known better. We both should have, but that's her business. It was a very close (figuratively speaking), intense relationship, but also full of complications and frustrations that, again, should have prompted one of us to give up, but it didn't.
Cutting to the crescendo, things progressed to the point that her partner left and it looked like we were finally going to get our chance to be together. Only, he decided to come back, she decided to keep him, and I ended up hurt very badly. Still, we continued on going through the motions, attempting to downshift to friendship for several months. But I was developing resentments and even contempt toward her. I admitted to that, and it was the last time we spoke.
DriGuy, I can relate to what you said about opting to keep the peace instead of getting into anything (or anyone) else that might disrupt it, even in ways that could provide momentary pleasure. In light of what I just described, I'm even more inclined to feel that way!
As I get older (closing in on 57), I think I'd rather take it easy for the rest of the ride!