FI and I are still finalizing the wedding party, but we've already starting getting a few questions about who we want to be in it (mainly from family and close friends). The best man and maid of honor have already been chosen and asked, and we know for sure his brother and my sister will be in it as well. FI and my MOH also came up with the idea that my little brother should be a groomsman, which I think would be a really sweet gesture. Based on our current list, we have 5 and 5 on each side with a list of alternates should someone decline when we do ask. Last night, FI's brother and his brother's girlfriend stopped by to see our new place and have dinner with us. FI brother's and his girlfriend have been together for a loooong time. They started dating in high school, broke up for a year or two, and then got back together about two years ago. They live together, function as a team, and talk about marriage one day. She comes to all of the family functions, and she even said last night that we were all family. However, she's not technically FI's SIL, and she and FI's brother are not engaged. They're also in their early 20s, so they're both still young and figuring out their lives and careers. I told FI that if he had a sister or a SIL, that person would have definitely been included in my BM list. Now I'm wondering if I should ask FI's brother's girlfriend since they've been together forever, live together, and she's basically considered family. What are y'all's thoughts?
For the record, she has not asked to be part of the wedding party. FI's brother asked last night who FI's best man was (awkward...), and then they started talking about the bachelor/bachelorette party. FI's brother's girlfriend asked if she was invited to my bachelorette, and we told her of course. A few sentences later on a different topic, she said, "we're family!" which made me think that I should perhaps consider asking her...
I'm learning with this whole wedding planning thing that it's very easy to make me feel guilty lol. Obviously that wasn't her intent, but I feel guilty nonetheless.
ETA: You guys are definitely right. List of alternates is a bad idea, and we won't have one when we finalize the list of people we want to ask to be in the WP. Additionally, FBIL GF's does not need to be included in the WP but is obviously more than welcome at WR events. Thank you for being the voices of reason!