Childfree ladies and afab people, when did you realize motherhood and marrying a man aren't for you?

I'm really curious. Because I realized I was meant to be childfree after all when I was sixteen years old, before that, I doubted my decision back then and kept on excusing myself with "Well, I'm young, still in high school, maybe I'll change my mind and end up do wanting them!" I idealized of wanting kids back when I was super delusional to think I'm going to have a great marriage only for me to grow up to reality that this was NOT the case for me after going through breakups, witnessing how my mom and dad would argue a lot and to this day, I'm proud of myself for not making it that far because I knew the outcome will make me extremely unhappy and I really want my own freedom back to do what I want to do. I would end up being full-time pissed off mother if I went to that path.

I know there are people out there who knew it at an early age like 8 or 10 years old so congratulations for them to not fall for something they were groomed to do and still keep making their OWN decisions throughout their life or some realized it later on in their life after arguments, abuse, and divorce from their ex-spouses in their 40+.

So, curious, how old were you and when did you realize motherhood and heterosexual marriage wasn't for you after all?