hi Enoughforme
I was intrigued by your question:
How do you tell her this without hurting her feelings?
Is it even possible? I guess the real question is this: are you able to tolerate the fact that it is entirely possible (and quite likely that anything you say will hurt her feelings if she chooses to interpret them in that way?
It is quite natural and human to take care of other people's feelings but it shouldn't be at the expense of your own. You are entitled to set your own parameters. As long as you are not deliberately impinging on someone else's then how they feel about it is entirely their own business.
We reap what we sow. if your mother has sown discord then it appropriate for her to deal with the consequences. This is the duty of any adult. It may be more realistic to work on a plan for tolerating how you feel if and when she feels her feelings have been hurt.
Ziggiddy