I can't tell you how many times I've put down the phone and thought, "Mom, can't you just say the polite meaningless thing?" I think I know how you feel.
I'd like to say I got over it, but part of me never will. The thing I think you can get over, though, is placing any faith in that reflection of yourself as true. Just remember that everything she says is colored by her limitations. She can only look at you through the lens of herself--so that means that she can't really see you at all.
It's sad, and frustrating, and sometimes funny all at the same time. But I think one of the better things you can do with it is put it here, say "AARGH!", and then go on.
I hope tomorrow is better for you.