I have some thoughts about relationships from an evolutionary perspective. I have heard it suggested that a relationship is transactional in nature. The hunter gatherer man can kill more dinosaurs than he needs to feed himself. He trades this surplus to woman, who can provide the children that he can't. Those hunter gatherer archetypes are still alive and well somewhere deep down in our psyche. The woman if she is going to take on the task of raising the mans offspring to adulthood she wants a long-term commitment. The man wants access to the woman (we all know where babies come from).
In your own case, you said your ideal situation would be to work one week a month to cover expenses the farm would not provide. I did the math on that it comes out to about $12k a year. Not a lot of money for smeone that wants an urban lifestyle. You said you wife is unwilling to take care of herself enough to bear children. Also, she is talking openly about divorce. As for the last item, that's none of my business. My point is nobody seems willing to bring to the relationship what the other wants or even what they themselves should expect. It looks to me like both of you have already given up on this and are only trying to avoid the pain of divorce. As an earlier post pointed out divorce is one of the most painful things in life. It seems to me you need to decide whether to invest that pain to make the life you want a reality.
On the subject of land and farming... I grew up in Cedar Rapids IA and currently live in Columbia MO. What passes for a green thumb in Iowa and what it takes to eak out a crop in Missouri are vastly different. That inheritance might buy more acres in Missouri. But, it won't be any more productive the land it would buy in Iowa.