Wish I had friends...

I'm not asking for pitty, just venting. I'm 27 yrs old and I can honestly say the last time I had real friends was Jr high school. As I got older the more I started keeping to myself and if I did let anyone in the minute I felt that they are betraying me I cut them loose. I tried to reconnect with ppl from my past but it seems like they have their own friends. The only person I have to talk to is my boyfriend but sometimes I just want girl time, you know hand out, talk shit, shopping . I'm trying to open up more but it's really hard cause I feel like I'm not fun or interesting to be around. People tell me to smile often but half the time I never realize that I'm making a sad or upset face ... ugh the struggle