I feel insecure.

Hi everyone.
I was in a relationship for 2 years, and almost 11 months ago, he left me without saying anything. After that, I had so many problems. I couldn't eat, I couldn't sleep, and I was desperate. Until recently, another guy with the same name as my ex asked me out. Well, I accepted but he left me too! I am not ugly, I have a job, I live in a good neighborhood, I am a PhD candidate at a very prestigious university. Why is this keep happening to me? I feel devastated and lonely. It is literally killing me.