I have a married guy friend. He is also my teams volleyball coach. As well as one of my daughters teachers. We have hung out on a few occasions. Mainly in groups though. like my volleyball team. He has held get togethers at his house and I have been there. His wife knows me. She is cool with it. The thing is out of the bunch of people in his friend group I am the one only one single. I always question if its ok.. I dont want anyone to feel uncomfortable. There has been on a few occasions that it was just me and him because everyone had left. which have been at bars where it was just me and him drinking.. Completely innocent of course. We text on occasion. He has at one point sent me a pic of himself. My friends have said that I should keep my distance because he is married. Keep everything on a business level.. as far as coaching goes and my daughters teacher. Can a married man be friends with a single woman? I believe so but a lot of people beg to differ.. Advice?