How to be more open? Should I come out to my best friend?

I'm 22 years old and it takes me forever to finally tell girls that I like them. I waited so long to tell the girl I currently like how I felt, that's now she's in a relationship with someone else. and I feel so stupid because I always do it. she told me that if I would be more open about my sexuality(only select people know I'm a lesbian) and if I don't look for love I'll find it. it's so hard for me to tell people that I like them because, I always used to get laughed at or have it thrown back in my face. and when I say I'm out to select people, I mean couple friends and that's it. No one in my family knows, hell my best friend doesn't know (and he's gay too). I went to tell that I'm a lesbian, but he gossips a lot (it's not as bad since we got out of high school). I would tell him, but he works to this grocery my mom shops to; and I'm afraid that he will tell her that I'm a lesbian. I don't think my mom would care (she has gay friends), but I would feel awkward because I still live at home and it might be different having a gay child. how can I be more open about my sexuality? should I tell my best friend that I'm gay? what should I do? any tips or ideas are welcome