Why do guys keep deleting me off Facebook?!?

[June]

Okay so in my life I've only had three kinda-sorta boyfriends. And all of them have either deleted me, blocked me or blocked me on chat on Facebook.

The first guy did it as a joke after we weren't dating anymore, his friend was on my account at a party and kept sending him annoying messages so the guy blocked me. It's been three years since and even still he has yet to undo this.

The second guy is a little more understnadable. He was from Italy so while he was in north america we hung and dated, but broke it off when he left. A couple months later he messaged me which lead to this rather flirtatious conversation. My friend asked me to copy our messages and send them to her however I accidentally sent them to him. He didn't say anything, and we talked a couple times after. Now he never goes online and I'm 90 % sure it's because he's blocked me on chat.

Now the final boy. I went out with him once, and I suppose I sort of lead him on because we made out, then he was trying to hang out again. It's been two weeks, and today he asked me if I was free to tomorrow. i didn't respond right away because I was busy but a few hours later when I got home I went to go say that I was and immediately saw that he was no longer my friend on facebook! He deleted me!

So my question is, what is wrong with me? Am I just handling things wrong or is it the guys? Honestly, I haven't got loads of experience with men and all those weren't serious relationships. So please, HELP!