So guess what, they can't get divorced! Massachusetts law requires that they be state residents to get a divorce, meaning they must move to Massachusetts and live there for at least one year before they will be granted a divorce. You would have to uproot your entire life and give up your job, your friends, all your ties to the state you live in and live in Massachusetts for a year or you are stuck being married to the person you no longer want to be married to. And you cannot divorce in the state you live in because no other states recognize your marriage as legal, so they can't end a marriage they don't recognize.
Basically if you're gay, and you go to the only state that will permit you to marry in order to marry, you are permanently married unless you are willing to uproot your entire life and move.