Well, I'm not a lesbian, but I didn't have my first date until age 22, and I didn't lose my virginity until the day before my 23rd birthday. Although most people have lost their virginity by this age, there are more than you probably think who wait even longer. It's not necessarily because they want to, but they do.
In my case, my OCD and panic disorder had a lot to do with it, but I was also fat before age 20, and I'm fat again (but have a boyfriend).
Don't beat yourself up...instead, try to figure out why it hasn't worked out. Why are you intimidated? Maybe you need to just try a few small moves, instead of big ones. Maybe hold a girl's hand, rub her back, work up to a kiss.
I hope you not only find a special someone soon, but that losing your virginity is a wonderful experience for you.