I can't see what all the fuss is about with gay marriage and I don't think it threatens the institution of marriage at all . Marriage , the way it occurs and what happens within it afterwards reflects the type of community the people come from religious or secular. Bahai marriage requires the consent of both sets of parents and if you don't get that you don't  get married. It is rigorously enforced. Consent from parents isn't required for secular marriages . Does that make a religious marriage better than a secular one . Nope.

If Catholics publicy state what is expected for a Catholic marriage i.e. its a heterosexual institution,good for them and the same for Muslim , Bahai or Hindu marriages : organised religions have the human right supported by their adherents to believe in their version of marriage. For them though and only them . They have no right to impose that belief on others . Problems occur when any religion wants to impose its beliefs about marriage on those who do not hold those religious beliefs. That is wrong and can give religion a bad name because religion is about individual choices made freely not coercing people to outwardly comply because one religion is dominant in a country. That type of religious expression was wrong , is wrong ,is dying out and will eventually be no more .

Besides , what is winning all the way,  is marriage itself, a religious institution in the first place and always has been , thats how it developed historically and if I was a person interested in having elements of my religious beliefs getting a wider take up in my country , and I am , equality between the sexes for example , I would and do feel quite happy that people in same sex relationships want to do what I as a Bahai have done but in a religiously specific way : get married! Good for them and it leads to better outcomes for kids in terms of money ,emotional stabilty and life chances .

Secular marriages and religious marriages are good ways to express love and great for kids and last longer than not being married at all!