Marriages unrecognized/romance disabled.

Marriage between quite a few of my Sims, those related by marriage or who share a distant ancestor,  are not recognized and romantic interactions are disabled. All of these marriages have children, but the game is treating each member as single (i.e. call pop ups re: potential dates when playing in another lot) while recognizing the parentage of the children. I'm not sure if the family tree update was meant to break marriages between distant relatives or spouses of other relatives. 

The marriages are not showing up as marriages in the family tree either. 

This behavior is occurring both with and without mccc. I do not use other mods.  Playing on PC.