Winnie
Its not a gay marriage it is a civil partnership. This enables gay couples to have more rights as partners in such areas as inheritance rights and pensions. Also as a legally recognised partner you have the right to sit at your partners death bed and be with them in their final hours. Something which heterosexual couples take for granted but gay couples could and have been denied by families of the patient when they have refused the accept the gay relationship, even if they have been life long partners.
What consenting adults do behind closed doors is entirely their own business. As long as both as willing and there are no children or animals involved and no one is hurt (unless they want to be hurt... but thats a different game altogether).