I'm an only child, as is DH, DS and DGS!
My mum wanted a big family, but she miscarried two after me, and then had a stillbirth, so they decided against trying for any more.
I wasn't at all lonely, cousins were a long distance away, so rarely saw them, but had lots of friends, one of whom is still my closest friend now, after 55 years!
I was painfully shy, but met a girl at Uni who changed me completely, she was very confident and outgoing and some of it rubbed off on me....thanks Barb!
I then spent my entire working life serving the public, so my shyness just evaporated and I can 'mix with, and chat to' anyone, in fact I may chat a little too much!
I'm not at all selfish and will happily share, but I do like to 'spoil myself' occasionally. good perfume, designer handbags etc. Maybe that's a sort of selfishness, although I never spend on myself until DH, DS, DDiL and DGS have been 'treated' first!
It was difficult looking after mum when she was very ill, it might have been nice to have had a sibling to share the stress, but I also didn't have to consult or consider anyone else when making plans for mum's care.
I'm fiercely independent, and have to stop myself refusing offers of help when offered, deep down I'd rather struggle and manage things by myself!
Fortunately, DH being an only child too, he understands, and we can happily spend days and evenings apart; as much as we enjoy being together, we both like our own company too!
All in all, am I glad I'm an only one? Definitely!!!