You seem to be living in utopian world. You have eulogised marriage and soulmate to the highest extent possible. It is a perfect role model life everyone looks for but very few get it. You sure need a shrink to get a dose of reality.
Husband-wife relationship atleast in our culture is so eulogised that we miss to look at the reality. We expect our spouse to be our soulmate and comrpomise everything we are to keep that thing alive. Relationships hardly accept we as we are. It is a question how much distance one is willing to go to keep it going.
You live with one person long enough, we can easily figure out his/her physical requirements like whether thirsty or hungry. It shows in the face. But the innermost self does not show in the face and we might live with each other for 70 years and still dont know the inner depths of onself. That is why I am saying, instead of looking at the soulmate through the prism of wife/friend and has to be another soul, look at oneself itself. Whether to reveal oneself is one's choice and so there is no better person that oneself to know better.
Am I being coherent? Or drifting?