So I read
This OK, my first response was to bring this right to snark.
Then, I said, OK, maybe I should just answer him.
First answer: The situation between her and her boyfriend is something she has to work out. Can you honestly say there's no one that you absolutely would not want your lady to be with? This is part of the poly deal. It shouldn't affect your future situations. And being poly isn't about needing to satisfy sexual needs -- or at least it shouldn't be.
Pulled it back as too snark-like.
Second answer: If you are asking for comfort, does that mean you don't want advice?
Nope. Snarky.
I think what he wants is: Oh, that nasty man, getting in the way of your poly lifestyle. It will all be OK.
Maybe that will work.
Oh, and he's a furry, to boot. Just sayin' is all.