Both my parents had died by the time I was 29, I’m now 55 and so it’s been a long time for me, I’m an only child as well and really have no really close relatives- cousins only but the ones I see are overseas.
I make sure I’ve got good friends around me. I’m very ‘good’ at keeping up with my friends and even if we don’t see each other for a bit, I know they’re there. I could put myself out there more but at 55 I can’t be arsed and am happy w my friends as they are.
I suppose the worst time for me on terms of missing them (more my mum, sorry dad, but we clashed massively - I don’t miss him now) was when I got married and had young DC. I had my PILs but never had a close relationship with them, but they were great w DC and loved them. I can’t fault them in any way for that (they’re both dead now too).
Also at ‘family’ times of the year when everyone is gather with their extended families is sad for me. DH has a brother so we see his family, but again not particularly close but we get on ok for a meal/xmas etc.
I also have young adult DC now who fill a family gap, it’s rare we all get together at the same time although they currently live here everyone is out at different times.
I miss my mum still, but I think that’s ok. I’ve made peace with that, but would like that big family Xmas which I’ve never had and unless DCs/their cousins have kids in the next few years it prob won’t happen.