Kromovaracun, the OP seemed to suggest that he wasn't affected by plans for gay marriage, and therefore the Catholic church shouldn't be. I think that's an illogical question - the church is objecting on its own behalf, not dabees' - so I restated it in another form that I hoped would highlight this.
None the less, the fact remains that the Catholic church - which was the subject of the OP - has no power whatever over my life. It has perhaps prevented jack from marrying within its buildings, I don't know.
It's a different matter for the Anglican church, which is unwarrantedly represented in the House of Lords. But as far as I know, despite the protests of the odd archbishop (and no doubt a lot of vicars), the C of E hasn't come out against gay marriage.