@PurpleSky300 You remind me a bit of me at your age (I'm GenX). Also an only child (of a single mother) and spent much of my childhood alone, - happily in a way, but I wasn't really socialised or given any guidance. I had no idea you were meant to want to get married and have children, no idea what a career was. Left school at 16, both parents happy as they didn't have to pay school fees anymore.
Then I drifted along for years, in low paid, zero prospect, jobs, at slightly glamorous London companies. Had boyfriends, always the ones who want to fuck you but not marry you. It never occurred to me this wasn't right, back then. If I ever thought about having children, which wasn't often, I always knew I'd never do it unless I were married, - I'd hated having a single mother, all my school friends seemed to have 'happy' families. Even then, I didn't actually want to have children.
At age 36 I finally got my act together and got a place at a good university to study for a BA, and I got a 2:1 degree. (This was only after very serious prodding from a friend who cared and saw that I was drifting - "You have to do something!")
Sorry to go on about me. But I wanted to explain where my advice is coming from.
My advice is, don't drift. If you don't want children, really don't have them. There is more to life than reproducing and living in a routine with a husband who, chances are, will leave you for a younger woman. Also don't get pets if you don't want them.
Enjoy the fact that you don't want children, think deeply about what you'd love to do, - really love - career wise. At your very young age anything is still possible.
The One is a fantasy, - the rescuer, the knight in shining armour.
When I look back at myself, I can see that I never wanted to be married. - I had a couple of odd offers in my 30s - And I think it's a fine thing not to marry and to have the freedom to be yourself.