I've been building toward a relationship with a guy who is wonderful in most ways. He's communicative, he's confident, takes care of himself, considers my needs, etc. We like one another, but we haven't gotten physically intimate. We have an intense connection that is has surprised us both, but we do not live near one another.

He has several other long-term partners. He works to avoid committing too much to any one person. He doesn't consider himself avoidant, but I've noticed that whenever we have a really deep chat or we acknowledge feeling close or bonded with one another, he'll almost immediately (like the next day) go see one of his other partners and be physically intimate with them. I think this is his way of relieving some of the sexual tension we feel, but it also puts emotional distance between us.

I have pretty much always been monogamous, and connecting someone who is not is new for me. Is feeling jealous/rejected when he goes to see other partners like this normal? Is it just part of nonmonogamy?