My parents have been married for about 24 years, most of which have been plagued by a meddling mother-in-law (My dad's mother). A couple of years ago, my grandfather passed away, and obviously this was a difficult time period for my grandmother, but even now, it is being used as an excuse by her to get my father to sympathise and huge amounts of time with her, in turn not spending much time with my mother.
My grandmother has never really liked my mother, and has not made any effort to conceal her opinions of my mother, who is honestly the kindest woman I know. Mum treats her with so much respect, and gets none in return. Now, my grandmother, who has no illnesses or medical concerns, is trying to get my dad to invite her to move in with us. This would be problematic as it would involve moving houses, as there is definitely not enough room for her, as well as my two siblings and I.
The main issue is, however, that my mother will have to spend every day with her, and when she insults my mother, she in turn insults me, because I do not want my mother to feel insecure or bad about herself as a result of the meanness of grandmother.
My dad takes my support of my mother as her somehow brainwashing me, which is quite ludicrous, because, at the age of 18, I have the capability to use my own observations and mind to make decisions and thoughts. My parents are arguing constantly about this, and when I have talked to my closest friends, they have told me it is best to stay out of it.
However, can I really just stand by and watch my mother be sad. I honestly can't envision living with my grandmother, as she can only be taken in small doses, and she lives 15 minutes away, so there is really no need to move any closer. My dad acts like a petulant child whenever reasonable arguments are brought up.
What should I do? Should I say anything or just stay out of their issues?