I really recommend you to ask Allah to get you a solution, don't forget the wife of pharaon has one of the best places in paradise because sh had no power against her husband so she asked God to help her out of the sins.
You must also learn how to talk to people, your objective is to save them from hell, not to impose your own opinion (because it's the way they perceive it). To proove your honesty to your self, do a prayer for your father after having talked to him, asking god to show him the way. This is something every person who does da3wa must do: pray to ask God to show the peson he talked to the right way.
Don't think you will save the world, the prophet didn't, and God told him he could not make people believers only if god decided they will be. So do your best, but remain detached and don't put too much rigid emotions in it, after all, you won't show the way more than the prophet did, and you're not even sure you will be saved (your own). So always talk without accusing the other, say only what you feel and what you suffer, never formulate by saying what others do to you (like: instead of saying to your father "you sell alcohol, you are doing haram", say "I'm afraid for you and how you will face God when you will die, I'm uncomfortable to eat and dress things that come from money God forbidden"
As long as the person is not agressed and feels he can help, he will help you because you show you are in a trouble. If at the opposite, you judge and accuse the person, he will be busy thinking of arguments to show he is not evil, and he won't care about your problems (because he's sinking, and because you didn't talk about the thing as a problem for you).
May God help you in this