http://exmormon.org/phorum/read.php?2,722576

because i have something to suggest:

If she is serious about wanting to not be so affected by her mother, then she needs to see a counseller who will help her seperate herself from her mother. This does not mean she had a 'bad' or smother mother relationship; she needs to be able to say 'no' to her parents and mean it. For some this comes very slowly. Her willingness to do this (on her dime, as it's a skill she needs to have for the rest of her life) and some time afterwards to see how effective she is at it, will show you how much she means what she says.

This doesnt mean she will be taught to dump her family. A counselor will help her set boundries appropriately and help be a support as she tests this out. It will take time. At the same time, read up on mormonism and see what you WILL be willing to give in on, to make peace with the grand parents.

Another way is to move a continent or 2 away from the inlaws. But that may not be practical.

Good luck and best wishes.