I've lost all the people I cared about. What to do?

Over the last couple of months I lost everyone important in my life. First my boyfriend dumped me because of some greek tramp, and then he didn't even have the decency to tell me the truth or to tell me this in my face, so he dumped me over FB. Then I found out my "best" friend has been lying to me about everything. She used to like my ex, or at least claimed so. Right before we hooked up, she told me she didn't like him at all. Then she was mad at me because I started dating him. Then yesterday she told me she was into one of my friends who I'm into and who's into me, and that she has liked him two months ago (when she claimed she liked my ex, and she didn't even tell me that). Now my ex is bitching around and telling some **** about me so many of my friends are acting really weird. There was this other guy who I thought was my best friend, but he told me he was inlove with me, but I rejected him and then he started acting like a total *** too and telling **** about me. Now I've lost so much of my friends because we are no longer in the same section and we barely meet. My other "best" friend told me that my ex didn't do anything bad to her personally, so she coulnd't have harsh feelings for him. And she is whispering all the time with the first lying *****. When I ask them what they're talking about, they laugh, high-five and ignore me. I have nobody. What should I do? How am I suppposed to be happy? Please help me because I've never felt worse. :((((((((((((((