Yup. A male friend of mine (Pres) hooked up with a male professor (J) who had become a close friend of mine (all while we were his students). My friend, the prof, a female friend and I all went out to a gay bar one night and the friend left my female friend and I stranded because he went off to get some.
The sad part of the story is that Pres and J had some relationship issues that devolved into a HUGE blowout in front of the class, and ultimately led to the end of my friendship with J, and his decision to... *ahem*... "leave" the university.