Lets see two girls trying to have the definition of Marriage changed so they can have a pretend Marriage. One pretends to be the husbands role and the other pretends to be the wife. They cannot consummate the Marriage or procreate. No where in nature does this occur. That is not my idea that is natures and evolutions idea. Here is the scientific observation. Lets create a lab scenario. Suppose all opposite sex attraction was suddenly gone off the planet. Now all you have left is the normal homosexuals. No opposite sex attraction equals no offspring equals the end of your species. Knowing that your behavior would cause the end of your species is considered abnormal.