This touchy subject came up often when I was an elder. Many older ones who had been together for 50+ years seemed to be broken by the prospect of not being with their former mate in the "paradise earth".
I used to try to comfort them by telling them that we just don't know how it will be in the "paradise". My reasoning was that in the 'new system' when someone is resurrected and they have family members there to greet them, there children will still be their children, their parents will still be their parents, grand children still their grand children, etc. That the only fleshly relationship that will not be the same is the marriage mate.? Marriage is the most intimate fleshly relationship mankind can have, originated by god himself, but it's the only one dissolved in the "paradise"? lol
just saying!