power of attorney?

I need some real advice..im in a big jam here..my grandmother just passed away in may, and my grandfather is now trying to sell the house my family lives in, when he has a condo of his own..just so he can blow the money on casinos and alcohol..is there a way I can get around this..I heard of something called the power of attorney, does he need to sign papers aswell tho? cause that wont work..but hes not in the right frame of mind all the time to make such big decisions..he wants us out by september 1st, and he just informed us of this..no time or anything to really move..its ridiculous..he also drinks and drives everyday..he spends anywhere from 800-1000+ on alcohol a month..also my grandmother told my father and mother countless times that this house is my fathers, not to move..its like he waiting until her passing to make the decision. and he wants me to move in with him and take care of all the cooking and cleaning and errands..he says he knows I dont like it but its to bad, thats how its working..and how its going to be, im 22 years old..I have a life of my own, I feel quilty enough about wanting to take legal action against him for his decisions..but I feel as if I have no choice with what hes saying everyday..he loves me I know, and I love him..but what hes doing just isnt right at all. please help me if you know what I can do..I live in toronto..thank you so much