Anyone had success in dealing with a hypochondriac / munchausen parent?

90 yrs. old and when mom gets bored or not getting enough attention she comes up with a new ailment and another doctor visit on the horizon. She has cried wolf so many times I don't believe anything anymore but must humor her in the event that for once the ailment may be real. This has become such a vicious circle and I don't know how I can ever get her to be truthful.
She's been obsessive about the medical profession as far back as I can remember and it's only getting worse. Mom seems to have no conscience or inkling that what she is doing is wrong in any way. The docs have told me "there is no sign of dementia", but I'd like to know if she is a sociopath.
Mom is quite healthy for 90 and I have come to resent the fact that so many out there are really suffering while she imagines ailments to get attention. I find this truly repulsive and smacks in the face of everything I believe in.
My mother disgusts me and I am at a loss.