It's Not Like I Hate Her

I don't get along with my Mother.
Not for lack of trying that is for certain!
We are like oil & water.
These days all that her conversation deals with is her health, which is horrid because she is morbidly obese and she has all the secondary symptoms and health issues that go with it.
I do NOT allow her to go off on that stuff with me. She always seems to want the upper hand like some type of one-up-man-ship that her medical issue are worse than mine. I being military disabled due to 2 near-fatal vehicle accidents overseas.
I have come to the point where I will not placate to her benefit.
If she wants to wallow in pity she will have that Pity Party alone! She can change her medical issues by not lifting a fork so often to her mouth! My issues are for life!
I guess when it all comes down to it, she is not and never has been the role model for her children, nor has she ever done anything to cause me to respect her.
She is my mother, I love her for that, but nothing else.