Hey mate
I think the key here is to talk yourself up. Don't slag her off back, just talk yourself up. Make yourself the centre of this all. She's talking about you and so are you.... it's like you're famous, film stars have to deal with people talking about them all the time.. saying good and bad stuff.... the angle is "I must be hot sh**, you spend more of your time thinking, talking about me than you do yourself" etc.
Soooo.... tell her this....
"You were right, nice call... I do forgive you. I understand it must be difficult to address someone like me. I get it quite a lot. People are nervous about communicating with the living legend the same way they would be if they met their favourite actor. I know that calling me 'skank' was just your way of overcoming the sense of being over awed that you were experiencing. I'll tell you what. Not only will I forgive you... i'll post you that pic, autographed. I know that'll really make your day

"
Bit long winded but this always works for me. I get into a fair amount of these situations and my approach has proved to be flawless, for me anyway. Hope this helps.