Thanks everyone so much, for all of the replies. I'm very upset that he is on her side, you can clearly see that it kills him to do that. We were best friends, and did everything together, but once I went to college and got a job, he got a girlfriend, and she controls EVERYTHING. She even walked into my room when I stayed there (for only a night) and flipped out saying how gross it is that she was using a pee pad and told me that I was horrible for bringing the dog home because it was "too soon", and that she and "your father" decided that once their dog dies, that's it..
She wanted to not let me stay but dad offered to "let me stay in the basement, and he will convert it into an apt.."

are you flippen serious? I really don't want to choose sides, and it's stupid that they are trying to make me feel guilty.
She could stay with my grandmother for awhile, but even then Idk.