I still have quite a few friends who are Christians, but they're mainly people from the first ever church I went to when I was a teen, before I got into the dodgy stuff, and they're all very nice indeed. I now live a long way away from there, but I'm still in fairly regular contact with a lot of them. They know where I stand these days, and they respect me for it. In fact, until fairly recently, I saw most of them at Greenbelt each year - an event which is as Christian or secular as you want it to be, and has plenty to offer anyone.
One year at Greenbelt I told a friend of a friend about how I'd left the church and become an atheist, and she acted like it was the biggest tragedy in the universe. I told her it wasn't a tragedy because I didn't think it was one. Her reaction was to offer to pray for me, which I politely declined, but on subsequent reflection, I found that really obnoxious.
At the height of my evangelical fervour, I can only begin to imagine how much it must have freaked out my parents. I know I'd go spare if one of my kids started behaving the way I did back then.