Why should I give a man years of my youth without anything in return?

I already know where this ''moving in together'' leads too. Many of us get attached and then due to our biological clock, we obviously want to form a family. I just broke up with someone I've been dating for 4 months (no sex yet) but wanted us to move in soon and continue the relationship for at least 5 years. I only needed to hear the words ''5 years'' and that was enough for me to walk away. I tried to reach a compromise but he kept with the ''no, at least 5 years''.

If I were to move in with a boyfriend, how do I know he's not going to get too comfortable and waste years of my youth for nothing? Besides romantic words (words prove nothing anyways, just words and promises mean nothing), how can I know he'll reciprocate and be ready to have kids within my timeframe, not his? He can wait 10+ years (unlimited) for all I care but I can't.

Everything is give and take. But honestly why should I give a man 5-6 years of my youth and wait on his timeframe? Why on his timeframe? Why should I be waiting for him if I'm the only with the limited time to have kids? Shouldn't it be the opposite... the person with the unlimited time should be the patient one waiting and if that means eliminating sex while we're just dating so beat it. I got more to lose if I waste too much time.

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the compromise I was giving to give was 2 years miminum and 3 years most but no more. I can't do more.
Why should I give a man years of my youth without anything in return?
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