Does my Fiancé's Brother's Girlfriend have to come to my wedding?

Yes, she is not a plus one, they are a social unit so they get invited together.

They are a social unit, so yes, you are obligated to invite her.

She is not a plus-one. That's his girlfriend. You address his invitation with both his and her name on it.

Excluding someone's partner is a good way to bring in additional stress and drama. Just saying.

Yes, you must invite her.

Yes she needs to come and be invited by name. You probably won't even notice that she is there.

Yep. And if you think for one second that you'll be more focused on her than your fiancé, I don't know what to tell you. Priorities, girl!

I think it would be incredibly rude if you don't.. especially to the BM. You guys are going to be family and don't want to start off bad. Besides.. your going to be busy anyway. You might not even notice her.

Yes. You have to invite all SOs of guests and they do not count as plus ones. Even if that weren't the case the Best Man should be able to bring a date.

It will be your wedding day. The only interaction you have to have is accept her polite congratulations and thank her for coming. Don't let petty drama get to you now, or you will end up thinking about it and bitter on your wedding day.

She's not a plus one as others have said. Plus he may end up marrying this woman. You need to stop thinking of it as his brother and girlfriend. They are a package deal. You should get to know both of them.

She needs to be invited to the wedding. You probably won't have to spend much time hanging out with her though, so don't let it bother you

Yes, she needs to be invited. You don't want to start your new married life with broken ties with your FH's family.

Yes. As a best man AND with a sig other, she needs to be invited.

Yes

I really don't think having her at your wedding would be adding any stress to your day. There'll be so much going on, you probably won't even notice she's there. All you'll really notice is your new hubby that day.

Uh yes, they are a unit, they need to be invited together. If you want to get to know FH's brother better, plan a day to get to know him. You're not going to be spending a solid amount of time with him OR her they day of your wedding.

Yes. They are a social unit and it would be terribly rude not to. My FH received a wedding invitation after us being together for 6 years and they didn't invite me. I am still holding the grudge...

Yes, but you're under no obligation to talk to her other than saying hi and thanking her for coming, and you don't need to include her in family pictures (unless they get engaged before your wedding).

Yes, they're a social unit.

Also, if your wedding really is October 2018, I wouldn't stress about it right now. They may not even still be together next year when you're sending invites. You could also use this time to get to know her / your FBIL.

Yup I would look at her as family instead of as a plus one. Doesn't mean you have to spend the whole day with her though

Yes, invite her. It would be rude to not allow your best man to bring his significant other. You honestly probably won't even have enough time to really interact with her on the day-of, so I wouldn't stress about it.

Yes invite her.

How would you feel if you weren't invited along with your FH to a wedding?