Here is another similar thread:
Who else doesn't want kids? | AspiesCentral.com
I recalled the discussion I just linked, but
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I too never wanted children. I am an "NT" although I have a LOT in common with many here at AC.
From the time I was VERY young, I remember just never desiring having kids or the idea of having a "family". I always pictured myself as having a career, & also hoped to eventually marry someone who would be a great husband/partner. I also always wanted to have pets. When I was very little I had one beloved baby doll but otherwise always played with a tiny people family & those small plastic animals (farm, jungle, dogs & cats, etc...) which I also collected. Meanwhile my sister had a bunch of different dolls & played with them all the time. She also said from the time she was very little that she wanted to have a large family when she grew up. Her desire & plan to have children never changed. She was also lucky to marry a wonderful man who is a terrific husband & father to the kids they both wanted.
As I grew up & older I still never wanted kids but I began to associate actual 'reasons' (which maybe someday I'll list) for not wanting them. All through my 20's & 30's some people - mainly work colleagues & strangers, not my own family or friends - would question & nag me about not wanting children ... telling me how I would be missing out, who would take care of me when I was old, & also wondering what horrible trauma had caused me to not want kids.
I always 'liked' kids & am very compassionate to anyone who is hurting or needs help, but truthfully I found very young kids to be a bit of an annoyance ..... loud, messy & inconvenient.

I did a lot of fun things with my husband's nieces & nephews, & was very generous to them, but small doses of time together is not the same as being with them 24/7. I was also never a baby 'lover' meaning someone who 'swoons & fawns' over babies.
Fast forward to my sister's first child being born. When she first announced to us ... SO HAPPILY ... at a family Christmas that she was expecting a baby, I was secretly sad & disappointed. I was happy for her but inside was so sad thinking that this is our LAST wonderful family (adult) Christmas as we know it. I pictured a crying baby & everything changing. I didn't share that with anyone except my husband because I knew it was such a selfish & hurtful reaction, but it was how I felt deep down.
My niece was born that spring, & I met her when she was a couple days old. I don't know why, but I fell in love with that little girl from the moment I held her in my arms. I absolutely adored her & it has never changed. (She & I are actually much alike & have always had a special bond.) EVERYTHING did completely change in our overall family after kids arrived, but I could not imagine life without them. When you love them they are a JOY, even when they are a pain in the butt or misbehaving.
I NEVER thought I would feel this way, but just a few years ago it finally hit me, Regret. And the thought that I had made a mistake in not having my own children. It does not depress me though nor is something I dwell on. It is what it is. And if I am completely honest with myself, the regret is for myself, selfishly, that I will not be surrounded in old age by children & grandchildren who love me.
I'm sharing my own experience in case it's helpful to you or others.
It is a
very personal decision. Kids are financially expensive, selfish by nature, demanding, a 24/7 commitment, & more. They are a LOT of hard work & the biggest responsibility in the world IMO. I'm sure you already know all that from your finance's children, & should you marry you will be a step-parent so not totally childless.
Everyone is different, & there is nothing wrong with not wanting or not having children.