I've dated a former fat woman
What was that relationship like?
I didn't want to continue seeing her because no matter what I say she always thinks that she is right.
It is good to be open-minded and willing date people of different sizes. However, if your partner was unwilling to listen and always insisted she was right, it was probably better to part ways. It is better to be in a relationship with someone who can be more understanding.
She was impossible to talk to at times.
Sounds like that relationship was doomed from the start. No one wants to be with someone who doesn't listen to them.