So myself (M30), my girlfriend (F28), my metamour (M42) and my date (F22) all met up to celebrate my metamour's birthday. Had a lovely time together, which ended in everyone having a more intimate endeavour together at the end of the evening. It was at that point the evening became sour for my date and I.

My metamour had a fantasy involving me doing abc, then afterwards he'd do xyz. Which was fine. The four of us had fun, but after I'd finished our girlfriend asked for my metamour to take her to another bed, where the two of them continued to have sex, excluding myself and my date. Which on paper seems fine, pairing off can be part of the experience. What really stung us was what she said in that moment... That she only wanted him and the rest of us weren't to watch or join in. We didn't expect to feel so cut by being excluded from the experience we'd decided to all share together.

The next morning, we both overhead their pillow talk (in the bed just next to ours) where she'd said she did this as a present for him, and that she'd texted other guys to come meet them (They'd made plans to have a date day the two of them) and do the same thing I'd done for them during the session. In that moment I'd never felt more used, as did my date. We felt were invited by my girlfriend specifically to perform a certain sex act, after which she broke up the group sex and demanded a private session in the same bed. And made plans to repeat the sex act with other guys.

I'm absolutely fine with being humbled. I come to the great Reddit Gestalt for more experienced mind's input on how I feel after this. Is this emotional pain I'm experiencing jealousy of seeing my lover express a deeper love to her boyfriend (they've been dating for 2 years and I and her only a few months). I'm hurt by seeing irl just how much deeper their intimacy is... And I should address it under this frame? Or was I used, my partner and I used to fulfil a sex act for the benefit of my metamour without being informed? Overhearing how she planned this and made more plans the next day was not a moment of sincere intimacy, but just auditory confirmation we were tools for her boyfriend's pleasure? I should address this under the frame of feeling objectified?

Much obliged in advance. I'd love to hear what you lovely, more experienced and open minded people have to say on the matter.

Humble regards,