I think my biggest flaw at the moment is jealousy. My bf and I have a pretty open relationship and I am usually very sure of myself and the strength of our relationship. But recently, I've put on a few pounds, gotten pretty pasty (you know, the computer glow) and I just don't feel as confident.
I also have PD (panic disorder), so I have an incredible ability to make up scenarios in my head if I get stuck on a negative thought. Over-analyzing, I suppose.
But, yeah...I'm working on it and we've talked it over and hopefully this will become one of the lesser flaws soon.