2015 was a complicated year for sex. Americans won rights, lost rights, gained some products, lost (even more of) their innocence about internet privacy, found new ways to be entertained, and were horrified more than once. As I wrote about these and other stories, my heart rose, and fell, just like yours. I was glad to have you along for the ride. I’ll be here throughout 2016, too—promise. You can also follow my 3-times-per-week tweets at @DrMartyKlein. Caitlyn/Bruce Jenner Famous athlete Bruce Jenner became famous transgender role model Caitlin Jenner. And now it seems like every third person is transgender,…