Now, in my younger days, I made the same mistake. But the men that I dated, who didn't "love" me in return, got me out of that habit. I don't know, maybe I became callous or colder because of my youthful experiences.
Robdar,
It appears we have something in common.
Six years ago, I allowed myself to get hurt terribly by someone I developed feelings for who didn't return them.
It was great fun when we got together but otherwise he was a jerk.
Never made that mistake again......