My ex and I always had a saying when it came to dealing with our extended families. . ."Main thing. . .complicated!" I know it is always a pain and people always end up feeling slighted, but if it was me, I would probably just let it go. She's your mom after all. I would ask her if she did well at bingo and that it was not a big deal. . .maybe you could go out together one day this coming week to make up for it.
Btw. . .just an example. . .my mom's sister is in town this week from California. So, last night my mom made a roast and had everyone over for dinner. Well, my one aunt that also lives here in town is always notoriously late. . .it irritated my brother sooo much. . .she called to say she was on her way and that she was bringing dessert. Well. ..my brother was an ass to her on the phone. . nothing new there, and my aunt said she wasn't coming if he was still there. . .blah blah blah. My poor mom! I just sat there wondering how in the world I ended up in THIS family. .lol! Really. . .I could have cared less when my aunt showed up. We weren't waiting for her to eat. Was it really such a big deal to stress my mom out like that? NO! Oh yeah. . .and there were 10 people. .6 adults and 4 kids (my 3 and my 12yr old nephew). There are only 6 seats at the dining table. . .and for whatever reason, my spoiled nephew always wants to sit at the grown-up table. I don't know why it has to be an issue. My brother kept asking my mom where everyone was sitting. . and I know why.

My mom finally said she could sit in the kitchen with the kids. I said. . NO!!!! The 4 kids will sit in the kitchen at the kids table. . .period! It's not like my nephew is sitting with a bunch of toddlers. My oldest is older than him. . .sheesh! He's a kid. . .he sits with the kids!