D likes to use the phrase "having skin in the game" to describe why some people seem more dedicated or motivated to a cause. Though it isn't a common phrase of mine, it is quickly gaining popularity because I think it can explain some money and relationship dynamics pretty well.
For example, in a previous post, I described a relationship dynamic involving a wife who is oblivious to how hard her husband works, gets bailed out regularly and has not really ever earned any significant money before.
Would it be reasonable to assume that because of that, she has not felt any real pain of having to save for anything in advance, balance expenditures, live according to a budget etc. etc.? Not ever having anything ride on her actions, hard work or behaviour?
Some people consider common law relationships to be in the same category. There is a relatively easy out, should you decide that it isn't for you. So is it level of commitment? Even the best relationships require a significant amount of energy to keep it fresh and fun and loving.
So what happens when one person in a relationship has more "skin in the game" than the other? Personally, I do not expect exactly equal ways of reciprocity because that may not be possible.
If the other doesn't make as much money, for example, it may not be possible to match but they can give into the relationship in other ways. This is a bit different if you are talking about the levels of wanting to be in the relationship. A bit trickier there.