This may be the least peaceful option but if it were me. I'd remind them of their impermanence and remind them that while, they may derive pleasure from my suffering, ultimately none of us last forever. That their desire to cause me pain will be short lived, and they will become the least of my concerns because everything is temporary. Idk what it is about saying that out loud to people, but it shifts their perspective a bit.. A more peaceful route would be to just ignore them but I know how easier said than done that is.