It is not childish to not want to marry and have children. Not childish at all. In fact, in some ways, it's sensible. Every single adult I know have split up from their partner (apart from the elderly generation). There's probably about 2 couples I know who have stayed together, and even then they don't sound all lovey-dovey anymore - they're just plodding along together. The couples I know who have only just got married or are just dating are the only people I know who are together (obviously) but I bet I know where their relationship ends up in a few years to come. About ninety-five per cent of relationships often go out the window in the end.
And as for having kids these days - it's no ''crime'' if you don't want any. Personally, I want to get married some day, but I've made up my mind now about kids - there's no way that I am having kids because I just know that they will be Autistic (knowing my luck), and I'm not bringing Autistic children into this world. And there's more reasons than as to why I'm not having children.
So you are not childish just because you decide not to get married and have children. My neighbour (who is NT) is 22 and she's been to university and has got a degree in law, and wants to train to be a lawyer. She says she wants a career - she doesn't want kids and she doesn't want to get married. All she wants is to to never give up what she's aiming for, and it will take time, but in years to come she will be earning very good money, and also doing something she has chosen to do. And she will make friends with other high-class people, and I think she will do far better in life than my other neighbour, who is only 17 and already is bogged down with 2 babies, and her boyfriend has already left her because he just had the 2 kids without even deciding on whether he wanted them or not.
Once you have kids, your life is over (so they say).
There are loads of other ways to live your life - kids and marriages aren't always the answer.
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Female