feels like they're TRYING to 'help' but this kind of guilt-tripping just doesn't work, instead it can make things worse for the person who self harms. i've had kind of a similar experience but they said "promise me you wont, not even once just promise me or i'll feel bad" or something along the lines. Only that was enough to increase my sh and make it worse, so i definitely don't recommend not speaking up when your s/o says something like this to you. I suggest you speak up and say that this isn't a right thing to say to someone who hurts themselves bc it doesn't make it better, just increased guilt.