I agree that it would be okey for them to stay together and decided not to have children or even adopt one instead.
But I doubt that is an option, since I have learnt from people living in Africa and also users on this forum that having children is an important part of the family culture there and not getting married and not procreating can lead to being socially rejected or stuff like that. In my opinion it is non-sense, since I am from the Americas; but I get how different cultures can be around the world.
I have learnt more about African culture since I joined this forum, tbh.
It's nice to know that you have lent other culture aside from your own from users in this forum and it sound great to be able to differentiate their culture and beliefs from yours and what is irrationally normal, Africans have hard a lot of horrible culture such as the killing of twins in some part of the continent until it was abolished by a western woman some decade/centuries ago.
Likewise also os the perception and believe in witch craft existence and the perception pf anyone not being able to bear they own biological kids as a witch in Africa a lot of things are intellectually and scientifically wrong but yet it's a standard of their existence in some cases.