Our (35f & 35m) friends (30-40s) of 1.5 years are slowly ghosting us and I?m not processing this well

A year and a half ago, we met a couple at our gym (which has since relocated). They invited us over for dinner/board games and we met a group of their local friends and became friends with everyone. Super nice. We don't drink or anything and neither did they so we hit it off great. No drama. We met up once a week, sometimes every other week during busy seasons.
About a month ago, we had our usual meetup where we had a potluck style dinner, played uno, dessert, very normal.
We didn't hear from anyone (we're all in 1 group chat) for 2+ weeks at that time, so we reached out asking how everyone's been. Heard nothing. Waited another week or so and my husband personally reached out with the husband who normally hosts 1 on 1. All he said was just been enjoying the weather, everything's fine and he'll let us know about the next meet. I decided about a week after that to reach out to the wife and invite them to an event we're attending and she never replied.
Then on Saturday, we were on our way home from a family party which is in the same general neighborhood as our friends home and sure enough, everyone was over there, all the mutual friends, sitting outside having a fire.
We debated stopping to say hello and chat but ended up deciding against it. Our feelings are pretty hurt. My husband thinks we should just move on and not contact them again whereas I would prefer constructive feedback or at least try to mend things if we did something wrong. I've been wracking my brain and can't think of anything at all.
What is the best solution here?
TL;DR Our friends stopped talking to us and inviting us and we aren't sure how to proceed.


Source.