Put simply, being married means you have entered into a legally binding contract. Although it is possible to get out of such a contract by divorce proceedings, this is a change as significant as entering into a business partnership, for instance. At a personal level, whether marriage impacts your personality or behaviour would very much depend on the individuals involved. In the past, women were married to their husbands and passed from being the chattel of their father to their groom, which could mean a significant change. However, modern property laws have altered this unfair status to a more equitable in nearly every advanced society in the world, so the change is less pronounced today.