Etiquette for inviting family members boyfriends/girlfriends

This is a real tough one because before I started planning my wedding I would've been offended if I wasn't invited to a family wedding of my other half's. However, now I realise that there's such a thing as venue capacity, and if the invites went out before you even got together then it's not as simple as just adding an extra person. As you've only been together for 5 months it's likely that they finalised their guest list way before you were even in the picture, and they can probably only invite a certain number of people because of venue capacity. Our venue physically only seats 130 people, so even though it sounds simple to say 'one more doesn't matter' - well actually it does! We can't have 131. We can have 130. So it matters. You must also think about the cost; every guest costs money especially if there's a sit down meal. Perhaps they are on a budget and can't justify new partners attending. You mentioned you're not that close, so I wouldn't really expect an invite to be honest, based on all of my points above.

Perhaps raise it with your boyfriend and ask if he can suggest that you attend the evening reception. There's usually a little leeway here with numbers. Probably the best compromise in this situation.

Two of our groomsmen have been with their gfs for months (one years) but we don't know them very well and our venue for the ceremony only seats 45 so they aren't invited, they won't fit. They are however invited to the evening reception, the one who had been with her partner for years is invited for the wedding breakfast, my BM has a boyfriend who she has been with a very short time so we haven't invited him at all currently, we'll see if they are still together when the wedding comes around.

Guest lists are an absolute nightmare, rather than a slight I imagine the bride and groom have just not thought about it yet as you've only been together a short time in their eyes. My friend didn't invite my OH to her wedding and we'd been together for seven years at that point, her budget just didn't cover it. There are lots of reasons why this may have occurred as has been said before in this thread, ask your boyfriend and see what he says.

Though it's all been said above, no you shouldn't expect an invitation. You've been together too short a time for them to invite you, and they'd most likely already sent invitations before you were a couple. Plus as you've said: you aren't close to them.

At most you can see if you can attend the evening do as a compromise, but I wouldn't push.

I would invite you if it was my wedding as I want my guests to have a nice time and not be sitting there miserable looking without their other half there but I do understand why people wouldn't invite you.

To be honest I'm of the opinion that if you aren't close with them you shouldn't expect an invite, especially if you're not sure they even know about you.

My fiances brother has just got a boyfriend and by the time we get married they'll have been together for 8 months but I haven't put him on the guest list because we just don't know him. It might be different closer to the time but at the moment its a no.