Of course she has sung. It is over.
Frankly it doesn't matter what some might do, or would do, or wouldn't do. If gay people want to get married, great let them. If you don't believe in gay marriage, great don't marry a gay person. It's no more 'illogical' than a politician or taxpayer lobbying for higher taxes to support a cause, yet in their last tax return 'only' paid what the govt required. It's a fact of life. Some gay people want to get married, some don't. Some straight people want to get married, some don't. But if there are protections and benefits offered under such laws, then they should be avaialbe to all Americans, equally regardless. There are probably 1,000 different reasons why a couple might choose to either get married, or not.
Those who oppose gay marriage will continue to lose at the Supreme Courts of the various states, and even the Federal Govt. It's just a fact of life.