This unfortunately, was the sign. Some people you know are a bad apple for you right off the bat... some don't show their true colors until after you have invested your heart into them and that is awful and there is nothing in life that can be done to prevent that.
Your response of "I don't want to know about" should be a clear indicator that you are not "okay" with it. If hearing of it hurts you, you are not okay with it and need to let the other person know that. Not that it would have changed anything in that particular case, you can't make someone not desire something they desire. But making clear what you will or wont accept will save you from being abused in a lot of cases.
For signs BEFORE you invest your heart into someone, things that show you might be making a poor choice becoming involved with someone.
*They are mean-spiritited. If someone is mean to other people easily, they will have no guilt being mean to you.
*They are self-centered. If they think their problems, their life, their issues, their needs come before yours all the time, thinking you will later some time get the favor returned is setting yourself up for dissapointment.
It sounds like all the girls you mentioned were mean, self-centered or both. Nice girls are everywhere. Many drop-dead gorgeous girls are nice, but also open your eyes to the girls that your hormones don't automatically draw yourself to.
A lot of young men are looking for the hottest girl in the room and could care less about the future or how she will treat him (not saying all the hottest girls are mean). Why not pay attention to the pretty girl, who may not be a supermodel, but that you find attractive and that treats you kindly.
I am not saying oh go date some ugly girl who will be nice. I am saying that there are many pretty girls that get passed up because they might not be the loudest or have their breasts on full display, or because they are not the one up on the table dancing... Look around with an open mind and heart.
Good luck.

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