message a guy I've never officially met?

So my mom has a coworker at her hospital (although he is a med student and she is a attending) and for the past month or so their coworkers have been joking about us marrying each other. (Because we are both the same religion) I have never met him but he has admitted to Facebook stalking me (as I have done to him... many times) and he had been invited to thanksgiving with our family and friends and he just canceled because his grandpa is sick and he's flying home to spend time with him.