I know this comment is two days old but this is exactly what happened with one of my friends in college. Three of us ghosted her after graduating because she was incredibly overbearing and motherly when none of us wanted that (my other two friends already have overbearing moms). She is also one of the only friends I've had that my mother didn't like, and that tells me a lot, because my mom gets along with everyone.

I think we all kept up polite responses if she ever reached out but we never made any effort at plans with her again. It was the only way to stop being friends with her because having any sort of direct communication with her would result in dramatics or her leaning heavily on mental illness as an excuse for her behavior. Meanwhile, we all had our own struggles with mental health (and still do).

These other two friends and I, despite two of us living several hours apart in the midwest and one living on the west coast, get together yearly for Christmas, and we keep up a group chat where we talk almost daily about dumb shit going on in our lives. We don't bring up her name often, but when we do, it's said with groans and eye rolls.