I would guess the main problem here is face-saving. If you can live along and get along, that is acceptance, even if they can’t say it out loud. So focus on the getting along rather than the acknowledgement.
I don’t know, but your chances improve if you’re consistently good to her & them.
Don’t give them an excuse to dislike you. Try to engage them socially, ask good questions, demonstrate that you’ve got a lot in common. Ultimately, it’s not healthy for her to be close to them if they drain her. She might try saying that.
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