Droves, I have always known. Obviosly young children don't think that much about it, but I can remember at age of about 7 or 8, being very worried at the idea that marriage might be compulsary, and my father assuring me it was optional! I also remember sitting with friends at about 11, all of us describing our ideal husbands. Everyone else was saying rich, handsome, kind, etc, my ideal husband was someone who worked abroad, and any came home occasionally to get me pregnant.
I have always felt sex just wasn't for me, and have tried to explain that to friends and family, but have only relativly recently realised there are official words for what I am, I am heteroromantic asexual, in other words I can feel mild romantic attachment to men, but not sexual desire. It is nice to know I have a definition. Up until I found that out, I did seem to be the only one. One close friend suggested once I see a therapist, to find out if I could have sexual feelings. I went twice, she said, to me if I'd never had sexual feelings by then ( age 32) it was unlikely I ever would. I stopped going, as I had my answer, and there was nothing alse to discuss, as I was perfectly happy the way I was.
I always knew I didn't want to be a wife, but also that I did want to be a mother. I did at one stage feel I should be married to have children, and tried dating. It was disasterous, I hated having boyfriends, felt miserable, and looking back, treated them badly. I quite young decided to be a single mother, and now I am.