Yes let her spend time with the kids on her birthday.
Resist the impulse to clarify things for her. Things like telling her you are not proud, and that she is the best thing that ever happened to you... stop saying those things. She hears “pressure pressure control control pressure"
Your last post is all about her. Focus on yourself and your kids.
You are very attached to R. You gotta let go of your death grip on the hope rope.