How to tell my Dad that I dont want to take care of Grandma anymore?

I need any advice I can get. Im just out of college and I have been living at home recently trading stock and saving up money to move out. Im doing pretty well. I have saved up almost $10,000, but since I donot have a w2 I cant really move out until I have well over $20,000 in savings, unless I have a day to day job. My parents are split, but both have said that I can stay until im ready to move out. My grandmother is 93 years old, and she needs daily elderly care. At her house there is TV with no remote, no internet, and she has dementia so mostly all she does is sleep and ask rhetorical and nonsensical questions. I didnt mind doing it at first, cooking cleaning and taking care of things around the house. Recently though, my inability to trade during the day has caused me to start losing money. Beyond that, I keep a regular news blog, and had an obsession with getting up to the minute news. I noticed myself becoming very depressed and almost suicidal because I was losing money helplessly, completely detached from what I felt was a comfortable daily schedule, and unable to talk to my Dad. I am still having trouble doing it. I want to tell him that because I have to spend everyday from 12-7 at her house, I forego eating breakfast washing and brushing my teeth in the morning because im trying to make my stock moves. I get very very very depressed by the time I have to leave, and then to sit in her house for 7 hours just makes it so that looking over my charts in the evening is a HUGE burden and no longer the fun stock picking adventure it used to be. I have a fear that my dad will make me move out if I tell him that I am being so negatively influenced by having to work with my grandma 40 hours a week, but that wont help anything. Just yesterday he came up to me and told me its so important that im in my grandma's life as she moves towards death, but honestly 40 hours a week? Im so lost and confused. I want my happiness and freedom back, but im not quite ready to move out on my own. My mom says that if I live with her then I must be at a job and not sitting around the house all day. When I trade carefully I can make 90-100$ everyday, and even on the bad days as long as im paying attention I dont lose that much. Its been hell recently with my missing so much because I am at her house trying to watch it from the phone and not the computer. Im sorry I wrote so much. I just wanted to give details. Does anyone have any advice on how I can get out of this mess? Maybe talk try to talk to my dad and reduce the amount of time. He thinks its ok because he pays me 100$ a week, but its hardly worth it. Any advice will help. Thanks!!