I'm 40, separated from my DC's father for 11 years, and I'm single. And mostly happily so. I'm not going to lie, sometimes I think it'd be nice to have someone to cuddle up to... or to share observations about people I know with. But then, I remember what it's like to find stray socks dried rigid with sweat in random places, and the way in which it's nice to finish a sentence without a louder male voice talking over me... and realise that, actually, I'm quite content as I am.
I'm also the oddity amongst my friends. Most of them have, at some point in the last 20/25 years, left their partners or spouses - and virtually instantly picked up with the next one. One of my friends who's a year older than me, had her third husband leave her at the end of April - and yesterday she was posting photographs of her "new man" all over the dreaded FB. Whilst I'm glad that she's happy, I do wonder at the example she's setting to her 17 and 14 year old daughters - and also to her young sons, too.
My DD (19) also flits from one relationship straight into another... which worries me. Where's the time to get to know yourself? The time to find out how to be an individual in your own right and not just "wife/girlfriend/husband/boyfriend of so-and-so"?
My ex, incidentally, moved straight onto another woman (she was the OW for a while, too, I suspect) and they're now very unhappily married with little ones. I feel sorry for them both. Him for being such a cliche, and her for having to put up with the rancid socks and the arrogant belief that he's better than all women simply because he was born with a penis...