This video got me about a year ago. Nothing super graphic, not at a slaughterhouse, not even any abuse. But the "simple" act of taking a newborn child away from their mother completely shattered any remaining dissonance I had about going vegan, personally.

https://www.youtube.com/watch?v=iL9QJEm_SJY

I will echo the other commenters suggestion to get some vegan creamers. Honestly, it may be worth considering cutting them off if they can't follow your rules in your own residence. There's plenty of food to eat that isn't meat (obviously); there's no excuse for them having meat delivered. If they can't go one week (not sure how long they're staying) without meat/dairy in your house, then they honestly don't care about your feelings.

I would ask them what foods they would prefer -- give them options like tofu, different beans, lentils, edamame, etc. Maybe make a soup with their chosen legume.

I would encourage you to compromise and """allow""" them to eat non vegan if you go to a restaurant. I understand this is really distressing, but with some people it can be helpful to focus on one goal at a time (e.g. no animal products in your residence).