Wow! Lots going on in your household. It must be stressful on everyone. I wouldn't break up with my boyfriend, even if my husband gave me an ultimatum. Does he plan to move out if you say no, or does he expect everyone else to move? Sounds like he is just freaking out at the moment. I might scale back a bit so you can focus on his needs, and give him lots of attention, but for me, no, I wouldn't kill a relationship at someone else's request like that. Especially when it was given as an ultimatum and in a time of pain.
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