I'm really sorry that your dad is causing this anxiety Kaily.
Us males can be proud creatures - my take is your dad doesn't want to admit the reality of his health - he's scared and doing things the hard way makes it easier for him to reconcile the comforting thought he still has some control over things.
None of that helps you - I'm sorry that you're caught between you anxiety and fear and his fear and stubbornness.
Please - keep reaching out -
this is not a drinking moment - this is a dealing with irritating insufferable selfish humans moment - but you're not alone
D