That's why you never make it official. Relationships don't need to be signed to mean something, that's just legal framework. Lots of people are practically married but not officially married. The rate of divorce and the things you lose with divorce, it makes sense to not make it official.
It's always the males with the most to lose in a divorce when it comes to finances/assets/etc. It's not very balanced at all. If you really look at it, nothing about marriage really benefits the male in the relationship if there is a divorce. The males lose a lot from divorce.