Everyone has the right to demand equal treatment from the law.
Not according to you, you're demanding gay couples be treated differently from straights
No I am demanding that same gender couples be treated exactly the same as opposite gender couples.
Bill and Bob- exactly the same in every way as Bill and Barbara- except that Barbara is a woman and Bob is not.
Bill and Barbara can get legally married, Bill and Bob cannot- they are not treated legally the same.
And that is wrong, government should treat all citizens the same. You aren't ending any discrimination, just drawing a different line.