I want another child. my hubby wants to wait

I wonder if it’s common. My hub and I have sex only once a month. Or maybe once in 2months. After we had our kid we are just not so into sex anymore. Or maybe it’s our long term rls of being together for 12years. Im no longer that bothered by this anymore as compared to the first few years when I just given birth. We still talk a lot and still close like soul mates. But recently I’ve been yearning to have a 2nd kid but he is firm about having just one child as he doesn’t want another kid to change the quality of our life or be tired and stressed up. Our finances are quite alright too. (However he did briefly mention maybe he might reconsider when our kid is very old, when reach teenage yrs) But I’m really not sure if I can wait. Occasionally I get depressed secretly and quite obsessed with those thoughts but cant express because I don’t want to pressure him esp on something he firmly rejected. Being not the highly fertile kind makes me more depressed and worried because I fear that when he finally open up to having more kids, it would be tougher or too late as we aged. My current kid was conceived only after 7years of unprotected sex naturally. Which is why I’m more worried. I really envy friends that could easily conceive and not worry abt this at all. I hope there’s a better way to release my sadness when the wave of depression comes every now and then. Anyone is going through the same and can relate to this? Pressure from family and friends around urging me to have another kid make it worst. But neither can I share with them my reason or feelings. How do u deal with it?