Something that always frustrates me is that homosexuality seems to be "singled out" as THE WORST sexual sin.
If we have to ask if we are allowed to be friends with someone who is homosexual, we also have to ask if we are allowed to be friends with people who have live-in significant others, people who do hookups on the weekends, people who watch porn, people who have flirty/sexual conversations on the internet (and many of them are married), people who have impure thoughts...
And this doesn't just apply to the non-Christian circles, as we ALL fit into this category in one way or the other. I've sat in church next to plenty of couples who are members, middle-aged (so they obviously know better), and living together without being married. I've known many Christian singles who regularly participate in hookups, porn, and going to strip clubs. And even if we don't do any of these things, all of us, at one point or another, can admit to thoughts we shouldn't be having. However, if someone is perfect enough to not commit ANY sexual sins, there are an entire host of other sins for which we all qualify, I'm sure.
I read a great story once about a Christian man who had befriended another man who struggled with homosexual temptations. He wrote about how other Christians criticized him and asked, "How can you be friends with a SINNER like that?"
To which, he gave this awesome reply: "How can HE be friends with a sinner like me?"
When I was going through my divorce, my gay friends did more to look after my emotional health than my straight friends at the time.
P.S. Maybe it's different for women, but I've never been afraid of a homosexual person harming me. I HAVE, however, been afraid of several straight guys and their intentions... But as I said, maybe it's different for me as a girl, or maybe it's just me and the people I've encountered.