I don't know what to do anymore

I've been lonely for the past 4 years. When I mean lonely, I mean to the point of not receiving a message in 6 months. The other day, I was playing with a friend and he said, 'From the outside it seems I'm your only friend.' In that very moment I felt really horrible because it is the truth (he doesn't know). I felt so embarrassed that I just told him names of old friends that I haven't seen in years.

I always have a hard time trying to make friends while seeing others having 'normal' lives. Since I was a child i was being told 'You always have a smile on your face' as if I'm always happy. Even now (I'm 22) my co-workers tell me the same, but I'm not happy, most of the time I feel worthless and sad. Every day, I just go from home to work and from work to home, no one invites me out. Always felt like I'm somewhat 'likeable,' since people at school told me secrets and trusted me, but I always failed to get real friends, not just 'school friends.' I only got a group of friends, and I ended up cutting ties because they started laughing at me.

I also see myself a bit boring, i have interest in a lot of things, but nothing interest me to the point to make relationships through that interest. Being introverted does not help either. At this point, I just think i'm gonna be alone the rest of my life