Ever since he came home from the party, he's been thinking about you.  He hasn't been sleeping well because he keeps having bizarre dreams that involve you.  He's become distant and very unresponsive; it seems that all he can think about is you.  But you're not his wife.  I am.

"I'm polyamourous," he said to me yesterday.  "I can love more than one person equally." 

"So you're telling me that you can love me and her at the same time, in the same capacity, completely equally?"  I made sure that I kept my tone as calm as possible even though I could feel the fear awakening deep down inside.

"Yes," he answered with that charming smile of his.

But you're not his wife.  I am.  I need his love.  You don't.  So back off.