To expend a little bit on Marriage being "special".
What makes marriage "special" to me, is when my wife and I decided to marry it was a clear statement to each other and to the "public" that we believe that our love is strong and special enough to carry us through the rest of our lives.
It is a vow that we intend to support each other during the hard times of life and that we think that the happy parts of life will be even better when enjoyed together.
If a homosexual couple feels the same deep love and is willing to fight for the recognition that they have the same special relationship, I think that this yearning rather emphasizes the special character of marriage, but by no means de-legitimizes it.
De-legitimizing happens by treating your own marriage as nothing special - and this can be true for heterosexual and homosexual couples.
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