My situation: mid 30's, got out of a domestic relationship mid-covid. By the time the pandemic ended, every single friend in my group had moved out of state for lower cost of living. My close family also moved far away or had passed away, and I found myself in a weird situation of living alone, working remotely, and spending 99.999% of my time alone.
I like being alone - probably more than most people. I would not describe myself as "lonely" but the lack of a friend/support group is a clear deficiency in my life and not one I feel easily able to rectify. All the usual meeting spots pre-covid where I'd meet people don't seem to really be the same anymore or I feel too old to really hang out at some of them (some trendier bars).
I am not religious so church doesn't really feel like an option but I am starting to consider it. Another issue is that in your mid 30's almost everyone has settled down and started having kids and only really prefer socializing with other people who have settled down and have kids, leaving you in an awkward place.