How can I deal with a extremely difficult and controlling grandmother?

I wrote on here once before. But not sure I really explained my situation. I'm 39 and a caregiver to my 93 y/o grandmother who raised me. I am in the process of moving out. My bf bought us a house and it's being fixed up as we speak. Was a fixer upper at a good price. Needless to say she has been a controlling and narcissistic person her whole life. She doesn't want accept I'm moving out and all help I'm trying to bring is not accepted. My father her son pays for her to still live in her house. My father retired 8 years ago and has no life. He pays bills for 2 houses. She is extremely selfish in the fact that everything in the house is hers and go buy ur own. She has been like this my whole childhood. I feel like I'm paying back my dad's debt for having his mom raise his kids. My dad isn't married so he doesn't have a wife to help him. I'm it. I'm turning 40 this year and if I don't leave now I'll be here till she dies. She won't get tested for dementia or depression. She thinks I'm responsible for her happiness. She won't let go of the control. Still cooks cleans and I'm stuck living in the basement with a toaster oven cause I'm to stupid to know how to cook or use the oven. I have been coping for the past year until I get out. I feel guilty leaving but she pushes every ounce of help I have gotten her. She had no money why my dad pays for her. She wants to die in her own home. My father need to sell her house at this point just to get back the last 19 years of taxes and bills. She never planned for her old age. She expected one of us to care for her. I have yet to be married or have kids cause I have put my life on hold for a ungrateful vein of a woman. I just want to walk away and wash my hands of it. Never says thank you like at my age I want to wipe her and put lotion on her feet. Woman my age are going that to their kids not their grandparents. I get bitter cause women choose to have a kid this life situation choose me cause I was the only one not married no kids and that was 5 years ago. No one ever thought hey maybe I want to get married and move out. We'll I'm doing just that and she pretends it's not happening. I trying to get to the point where I'm gonna be ok when I move out. The guilt is so much. I did the best I could. At her age she is spoiled. She gets to FaceTime with my cousins and her other grand kids and great grand kids. Knows what Facebook is. She was in the army so enough said.
Ahh sorry just needed to vent. All over the place but just had one of those mornings after reading other peopleside stories I just wanted to add mine. Any advice on anything will help.