What's the point of living when you are such a big loser?

I have been depressed over the past few months and I feel like a big failure. My biggest problem is that I suffer from social anxiety, and sometimes I act weird (mouth gets dry, sweaty palms, nausea etc) in social situations where I feel uncomfortable... That's why I am an introverted person and have a difficulty in making new friends. I had some friends though, but in the end I realized that they weren't real friends as they betrayed me (one of them was stealing money from me, some others stop calling me). Now I feel lonely. I am 18 and I have never been in a relationship or kissed a girl. It's been a year since I started talking with a really nice girl and I fell in love with her but she is not interested for me, despite the fact that she showed some interest in the beginning. I spent a lot of hours on Facebook, trying to make some new friends but no one cares about me, what I post or what I write, Last week I created a fake girlfriend and a fake friend to gain some attention. I did, but I felt ashamed of myself... I feel really bad and I think that people like me deserve to die...