What a topic to come back on. Look this is not complicated. Just like with interacial marriage back in 1967, the state is not going to tell consenting adults who they can love (okay polygamy is a whole other topic that I may explore someday).
Marriage carries with it a whole bunch of rights that just cannot be conveyed through a "domestic partnership" or a live in relationship. Rights of inheritance are based on the concept of "marriage." Did you know in Maryland, you can only give your crab license in your Will to a spouse. Not your kids, not your longtime love, your legally recognized spouse. Now Maryland is the home of crabcakes so this kinda of an important thing.
As the Windsor case showed, inheritance taxes between spouses are lower than between unmarried partners. To the tune of hundreds of thousands of dollars in that case.
Maryland had fun with this idea. We actually had gay divorce before we had gay marriage. I find that hilarious. It's just a quirk of timing. Maryland took the "full faith and credit" clause of the Constitution seriously. If you got legally married in another state, you are married in Maryland. If you are legally married, you can get divorced then. Not the big of a leap of logic. The only marriages Maryland doesn't recognize are common law. And that's probably because they are a pain to prove. It takes more than just someone saying "hey I'm married." The Court of Appeals decision came down in May.
It wasn't until voters approved the referenderum the following November that we got gay marriage. Unlike some places (uh-hemm Rowan County, KY), the clerks even made the licenses available before the January 1 effective date so people could get married on New Year's Eve. Awwwwwwww.
No one is going to be divorced from their opposite sex spouse to be forced to marry a same sex partner. It is highly unlikely churches will be forced to perform gay weddings against their wishes (not all churches oppose gay marriage, by the way) since the wedding itself is very much a religious function not an act of the state. But here in Maryland, the licenses have been issued for a couple of years now and the world has not ended. I doubt it will wreak havoc anywhere else in Maryland.