Nothing's wrong with you!
The same thing happens to me all the time. Certainly don't judge yourself on how ppl at the bar treat you!
Maybe you just need to find a new place to hang out

Especially if it does affect your self-esteem.
I know it sucks, but just remember it's nothing you're doing. What happens when you take the first step and start a convo?
I'm sorry I really don't have much advice since I go through the same thing!