My ex thinks I am a expert in flirting.
Is that because you think you're better than other people?
I don't view myself better than others. I have never said that about myself.
It's nice your ex feels that way, but I feel it's best to not get too invested into their words. They are an ex for a reason, and you wouldn't want to go back to that.
I know, I'm just curious what I should do about it.
I could see how her response is a little confusing. I think overall her saying you're an expert and flirting isn't a bad thing overall. There's nothing wrong with being good at flirting.