I Dont Want Kids

Why is it that whenever I say I don't want to have kids, people brush it aside and say "Oh that'll change" "That's not true" "You'll regret it." Like seriously. It's not a crime to not want to have kids. I'm not decreasing the value or sustenance of my life by not wanting to have children. Either people get angry at me or don't take me seriously. I've met 50 year old women who have never had kids, were content about it and people are STILL TELLING THEM that they will change their mind or that they made a mistake. Why can't people have respect for my opinion on what I choose to do with the rest of my life when I respect their choice to want and create a family? I understand the miracle of birth and the love between a mother or father and their child, and that's beautiful. But that's not what I personally want. I've had this opinion for over 10 years and I'm tired of people invalidating my feelings because I'm young and it's an unpopular opinion or norm. Fuck man.