Frank Bruni does an nice job of addressing the church's odd stance towards homosexuality. But he quotes the Cardinal Timothy Dolan, Archbishop of New York, who clarifies what is allowed for homosexuals.
“You’re entitled to friendship,” he went on, laying out the ground rules for same-sex longings and pairings. As for sexual love, he added, “that is intended only for a man and woman in marriage, where children can come about naturally.”What Bruni glosses over is, for me, really the most absurd dimension of the church's opinion on sex of any kind: sex is not meant as a tool for pleasure, intimacy, joy, or celebration. Sex is meant for procreation. Only. Gay sex is always wrong because they can never procreate. But what gets buried in that condemnation is this: heterosexual sex is also wrong if the couple is, for example, using contraceptives.
To be fair to the church, this opposition to sex not that absurd in a world of medieval realities, when childbirth is so likely to end a mother's life, when children almost inevitably were conceived in numbers guaranteed to put a strain on any family. Sex for pleasure in the medieval world is absurd (and yet of course it happened). The cost is simply too high. But of course times have changed.
This is probably the biggest reason the church's stance on homosexuality will change. It is based on an opinion of sex that is shared by almost no one - gay or straight - and based on a reality a thousand years old.