Hey man.
I'm 25 and from the UK. How's it going lad?
Here's my thoughts and It might hurt but I'm going to be honest...
It seems like you have resentment toward your Dad. Though I can imagine a negative father will make things hard (been, and am there) there's no justifable way to blame him for where you are, despite the obvious loving duty you have towards him. Realise that you are your own person and your needs come equal to his.
Perhaps look to move out in the future? Even with your disablities you could get a casual bar/warehouse job to pay the rent?
Take care bro.