I question your logic and I even find it a little terrifying. When they come to define citizenship, I just hope I meet their criteria.
Let me spell it out for you. Excluding a handful of states, marriage is CLEARLY defined as a union between one man and one woman.
Can gays participate in that institution? YES!
Do they want to do so? NO!
Why? Because the requirement demands that the spouse be of the OPPOSITE SEX.
Does their desire not to do so mean they're being deprived of the "right" to do so? NO!
Same goes for people who like polygamy.
Can they get participate in marriage? YES!
Do they want to do so? NO!
Why? Because the requirement demands only ONE spouse.
Does their desire for multiple spouses mean they're being deprived of the "right" to do so? NO!
If marriage were defined as "a union of two people who love each other" (or something along those lines) and gays were not being allowed to participate in marriage, THAT would be a denial of marriage "rights".
That's why I say: Gays are NOT being denied the right to marry. They are being DENIED the right to change the definition of marriage itself.