Navy Pride, do you not understand that this issue is brand new to most people? The people didn't grow old and decide to become against same sex marriage. Those who are against it have always been against it. People don't just get a family and decide that same sex couples don't deserve the right to marry after believing at one time they did. They never believed they deserved that right.
The younger generations now are not going to be against same sex marriage later in life in nearly the same numbers as those older generations now are. It doesn't work that way. Look at those against interracial marriages (and if you say one word about it not being the same thing, I will know that you aren't even willing to pay attention to the argument being presented). The number of those against it were huge 50 years ago. Now, the number is very small. There are still some, even younger people, that are against interracial marriage, in both races. But a very big percentage comes from those who are older because they are more likely to be taught that bias against something and hold onto their beliefs than the younger generations.
It is very, very rare for someone to be for something like marriage equality, whether dealing with race or sex and change their mind on it. It just doesn't happen in nearly the amounts you are suggesting.
And if you believe it does, then tell me, when were you for same sex marriage being legal? Who do you know who was ever for same sex marriage being completely legal and who is now against it? If anyone, why did they change their minds? What was their reasoning for it being legal first?