Broody but he doesn't want another 💔

Hi everyone, I've been feeling broody again after having my son almost 11 months ago. I would love to start trying later this year but my partner of 8 years said he doesn't want another. I would love to give my boy a sibling to play with and grow up and be close with. My partner is an only child and he just doesn't get it. I have 3 brothers and 2 sisters. I haven't been pressuring him as I know it's unfair. But how do I get over the fact that I will probably never have another child? It breaks my heart, I don't want my boy to be alone when we grow old 😢 I asked why he doesn't want any more but he never seems to have an answer? He loves our boy to bits! We own our house, we have a spare room, we have 2 cars, both in secure jobs... I don't get it 🤯