I've had a terrible love life for the past 4 years.

I honestly think there's something wrong with me. Or my Ex hexed my love life. Ever since freshmen year of college when I officially broke up with my high school sweat heart of 4 years, my love life's been shit. I've been played left to right and right to left. Man I've been going through so much pain these past 4 years. (BTW I'm a senior in college now ) I think I have become such a bitter person. I honestly think there's something wrong with me. I've only had one bf and after I broke up with him it's just been flings that never work out. This saddens me because I've been so miserable lately and I'm tired of being like this. What should I do ?