that sucks bro
i'd say you should threaten to tell your entire family he's a cigarette if he keeps going on doing that
rape isn't okay but neither is outting someone to the family when they aren't comfortable with telling them yet
that could seriously hurt their relationships and is going a bit far
i'd say push back with violence or pepper spray before you'd think of going that far. the pain from a bruise or eye irritation hurts but at least it's temporary and can get the message across, his entire family could possibly just turn their backs on him if they're that bad, or worse (send him to a facility where they basically hold him there like a mental patient until he admits he's straight and homoloveuality is a sin etc etc.)