To deliberately use someone's vulnerabilities against them is to commit a great blasphemy against intimacy. Anyone who is willing to do that under ANY circumstances is not someone who deserves my trust. I consider it to be a deep emotional violation, as much the inverse of positive sharing as stabbing is the inverse of petting.
I think I am capable of hitting someone in rage; it's not likely, but if they are attacking someone I care about, or if I cannot escape and cannot otherwise stop them from hurting me, I might hit a person. I do not think there is any way I could possibly use a vulnerability shared with me in trust to attack someone. That is fucking evil. I wouldn't do it to the person I hate most in the world. I wouldn't do it to the fucking Koch brothers, and I'd cheerfully watch them drown.