Liking guys who treat me like Sh!t... why do I do it?

I feel like I am strangely attracted to guys who treat me bad, every guy I have ever liked a lot has treated me bad, and the one who hasn't treated me bad... he actually treats me amazingly, I just wait for him to treat me bad. the first guy to start this cycle was a guy I met when I was 17 (he was 22), he stood me up 3 times and just stopped answering my texts, and I tried so hard to be good enough for him. When I finally did see him again he pretended like he never knew he made plans with me. The next guy was a guy I just feel HEAD OVER HEELS in love with.. unfortunately he had a girlfriend.. he took me out on dates and treated me so good then he just started ignoring me... I ran into him after about 3 mths and we exchanged numbers and I messed around with him, by that time his girlfriend was 5 mths pregnant) I (again) would have done ANYTHING to be with him, I wanted to be with him more than anything in this world, and even now a year and a half after he used me and treated me like crap I still think about him EVERY SINGLE DAY and I miss him a lot. The third guy was a guy I met online, he was nice and cute and wanted a family like me and when I told him I didn't want to have he called me a slut and the N word... the fourth guy is a guy who is in a fraternity on campus, this guy is not even cute.. yet I let him treat me terribly. All he ever talks to me about is hooking up with him, yet in public he completely ignores me (I haven't hooked up with the kid... yet) I don't understand why he ignores me in public. And finally a guy who is different... he's AMAZING and he treats me good and wants to be with me and I like him and want to be with him, the only problem is I feel like I am just waiting on him to treat me badly. I don't want it to happen but I know it will. I want to have faith in the kid of guy he is but I can't because I have seen guys start off super nice and get mean, and I'm not saying that if he did start treating me bad I would dump him, because I never want to be alone and so I would probably just stay and deal with it. I am just worried about everything all the time and I don't know what to do.