I have suicidal thoughts but would never go through with it because I know how much that would hurt my parents. I fantasize about them dying so I can be free.
Why do you want to be free?
Specifically my father is a burden to me and I want him to die.
That is very wrong to wish your dad was dead. You shouldn't think such things. That's very awful.
It's fine as long as I'm not the one killing him.
You shouldn't wish for your parents' deaths regardless. Stop being so selfish.