Why do you believe that he doesn't? What does it mean to truly love someone?

It just seems as if marriage doesn't have the meaning to it that it does for you.

Marriage is an obligation, that puts pressure on people and can end relationships regardless of how much those individuals are in love. Furthermore, there are responsibilities and societal expectations that come along with the institution of marriage. If not for the responsibility as a surrogate decision maker in the event of emergency or incapacitation and the tax benefits, I'm not sure I would care about marriage myself. The relationship between me and my partner is not defined by how society references us.