My partner can be very vain at times. I jokingly mentioned disliking their cocky attitude when we first met. Then I brought it up seriously when we had been dating longer. Their excuse is that they used to have no self esteem, but they lose weight and now they would rather be over confident than not confident at all.

I have had someone use this same excuse before for their vanity. I don't know why they see it as being so black and white-Vain or no self esteem.

How can I deal with their vanity? They often talk about how good they think they look etc...so I have tried to compliment them less.

Tips?