Is it ever okay to ask if your partner can join a private dinner?
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I (26F) have been with my boyfriend (26M) for 2 years. One of my closest friends (26F) invited me to a graduation dinner at her house. It's not really a party, more like a dinner celebrating her graduation with her family and a few close friends.
We're a trio of best friends, they've known each other for about 10 years and me for 5. She invited me and our other friend in the trio, but she didn't invite my boyfriend or our other friend's fiancé. Because of that, I think it was intentional that partners weren't included, probably because it's at her house and there are limited seats/food.
The only thing making this awkward is that, by coincidence, my boyfriend and I will already be in the same gated community since lunch time visiting other friends. So while I'm at this dinner, he'd be hanging out elsewhere nearby and then we'd meet up afterward (he also prefers that I don't head home alone at night, the gated community is quite far away from my area).
My boyfriend thinks that since my friend and I are so close, it wouldn't hurt to ask if he could join the dinner. I feel like asking puts her in an awkward position. Since it's a graduation celebration at her home, I feel like the guest list was probably planned intentionally, and asking if I can bring someone who wasn't invited seems rude, especially since both me and our relationship status rank "lower" than the girl whose fiancee isn't going.
So my etiquette question is: Would it be rude to ask if my boyfriend could join, or is that an acceptable question between close friends? I usually would never ever ask, but the fact that he'll be basically next door + him telling me that it's not a blunder is making me question my kneejerk reaction.