While I may agree with you that the best companion could often be your spouse, I may differ with you on your expectations from your companion.
To expect a companion to look after you or your children is not fair. while I am all for doing this together because you are a family, a team.
A companion is one you completes you and brings out the best in you and you do likewise.
You work together as a team.
That is how I see this relationship.