I would suggest taking her to another vet for a second opinion...SOON. It seems a little odd to me that for over two years, your vet hasnt told you what it could be, how its caused and whats gonna stop it....the fact that he keeps sending you home with a tube of cream, makes me question your vet - A LOT... JMO.... I just think thats unexceptable and would not stop until I got the right answers to my questions. And the fact that you can see it bothers her, would definately have me concerned... Please keep us posted