First -- of course relationships are more complicated than that, and all of them have the bits I am listing -- I am suggesting that the specific dualities give more focus to them, though.

From the functional pairings:

Se - Ni: We want to accomplish the same goals in our lives.
Ne - Si: We have fun exploring the same things and sensations.
Ti-Fe: We share the same ideals and want to make each other laugh.
Fi-Te: We want to understand each other and find the same kind of information useful.

So, from that:

INTj-ESFj and ENTp-ISFp: We have fun exploring the same things and sensations. We share the same ideals and want to make each other laugh.
INFp-ESTp and ENFj-ISTj: We want to accomplish the same goals in our lives. We share the same ideals and want to make each other laugh.
INTp-ESFp and ENTj-ISFj: We want to understand each other and find the same kind of information useful. We want to accomplish the same goals in our lives.
INFj-ESTj and ENFp-ISTp: We have fun exploring the same things and sensations. We want to understand each other and find the same kind of information useful.

I am suggesting that, very simplistically, these are the points that, when they are not met, are most likely to cause a failure in the relationships of these types.

For instance -- let us take Slacker Mom's marriage (ENFp-ISTp). I do know that she doesn't share his enthusiasm for cars and such -- but surely what I described works in other things, on other levels?