Many one on one friends but not really part of a group. Anyone else in this situation?

I seem to have many friends, but they’re not mutual. For example one is a school friend, another is from college, one from work, one from elsewhere, etc., and each one of them have their own circle. But that’s not the case with me, and sometimes it gets frustrating when there are weekend plans or other activities. I’m not complaining, but rather just wondering whether it’s just me or are there any of y’all like me.