Start working on yourself so you can get successful quickly and move out and live on your own terms. You're still young and I wouldn't risk the hardship of getting into constant conflict with the status quo because that's just gonna slow you way down, unless you feel strong enough to handle it. You have to make a choice and live with the consequences. Getting all vegan in their faces might piss them off and make life very hard for you. Personally I made the choice to just fuck them and be vegan, but I got alienated from my family as a result. But I don't care much because I'm emotionally resilient and have worked on myself. Some people can get kinda sad though so you have to make a choice and deal with the consequences.