Gay and Catholic an oxymoron?

Andrew Sullivan at The Daily Dish has a disturbing post about the aftermath of the Maine decision to repeal a law allowing gay marriage:

"After Maine, where the Catholic church actually organized a second collection to raise money to prevent gay people from having civil rights, the situation shifts again. Using a tax-exempt church to raise money to defeat the civil rights of fellow citizens is not too shocking in the age of Benedict. . . . It is time to acknowledge that the Catholic church hierarchy can no longer pretend that it isn't the active enemy of gay people and our families." Sully is accurate on the second collection, requested by the bishop of Portland, which covers the entire state.

Sullivan goes on to quote a letter from a gay Catholic to his pastor about leaving the church.

I admit that I find a second collection taken up during the liturgy to raise money for a political action to be a profound abuse ot the eucharistic celebration. But beyond liturgical abuses, one has to wonder if there is a way for the bishops to advocate for a traditional definition of marriage without completely alienating their own members who are both gay and Catholic.

Or is it true that being gay and Catholic is no longer possible?