No one else in family understands. My nan is showing all the signs of dementia, she also has random outbreaks where she just cry’s her eyes out, my mother suggested moving into my nan's house to help my uncle support her but she lost it and thinks everyone is against her. I’m the only one she’ll speak to now. I don’t want to jeopardize the position I have with her now but I can’t see her like this, I just want to help. Any advice?
Do not let yourself be guilted or talked into giving everything up to take care of your Nan. If this is your mother’s mother, your mom needs to step up to take care of her or make other arrangements for her care. At the least, she needs to get Nan to the doctor to see if there are any medications Nan could take to control her crying jags and anxiety.
You can help take care of Nan, visit her and be with her, but I wouldn’t move in.