Your parents probably have a personality disorder or two. Parents sometimes want to give their children everything they have even if its not healthy; they think they are being heroic and will remind you of all they have given you. No you are not being rude for declining to accept. Remind them you have not accepted. Don't take the blame. Don't let them plant a seed of doubt in you because those things grow really big. Try not to hate. Hell is a place of loathing. All loathing is self loathing. It doesn't start out that way but it always ends up that way. Your sibs are probably suffering like you are. Are you too old to be adopted? Have you ever read Pippi Longstocking?