It's very possible you feel more secure when you are around married men because they Aren't single. Gauge yourself around those you deem single and see if you aren't flaunting those awesome qualities you have ;) From what I've seen most people who can only pick up people already in a relationship are just too careful about how they act around the opposite sex, yes it's important to not overdue it, but if you're not really showing who you are you might come across and bland and conformist.
I've heard the key is to not give up ^-^ good luck
I've heard the key is to not give up ^-^ good luck