I think it's important to remember there are 2 issues here. There is the individual, and their sexual orientation. I am a shop steward at work, and have on several occasions challenged individuals for expressing view about a person because of that persons sexual orientation. I am able to, and have, defended an individuals right for them not to be treated differently, or picked upon and bullied, because of their sexual preferences. That does not mean I have to agree with what they do. It's a bit like a Christian believing a Muslim has equal rights to their own to worship and carry out the requirements of that faith etc, without having to subscribe to the beliefs of the Muslim faith (if that makes sense?)
I saw two homosexual men kissing many years ago in a doorway in our local city, and I felt it was deeply wrong. But they still have (AND SHOULD HAVE) the right to behave that way should they wish.
I think an area of confusion is often that racism, ageism etc, is wrong because a person can not do something about their race/colour/age etc but people do have a choice about their sexual orientation. Therefore it is OK to have a go at them because it's their choice being attacked. "I mean lads, lets face it, there would never be any lesbians in the world would there if they had all met us 10 years ago!" - yeah, really. Hmmm, talk to them - is it a "choice" or just the way they are?
As I said, I'm not comfortable with seeing displays of homosexuality, but I can happily work along side a person who is homosexual, and get on with them fine. Where I find it a challenge is in looking at my own children. I have 3 young girls, and I do not know how they will develop in the future. If one of them wanted to enter into a civil partnership with another girl when she was older would I photograph the event. You bet I would - but I would find it really, really challenging on a personal level, but I wouldn't let my own beliefs cause me to miss out on the happiest day of her life. Would I be happy seeing any physically displays of affection, definitely not. But I think that what is important is not to judge the individual for their sexual preferences, but to respect it, even when we do not share that view.
I hope my rant has contributed to the discussion. Rant over.