So...I read a little about communication today and reread the boundaries part of Cadet's post. So here's what I did tonight, after our S went to sleep.
First I asked if it was an okay time for us to talk. He said yes, and walked over to the opposite couch to sit. I told him that our S had mentioned that he had his friend over for supper last night and that I was confused at first thinking it was something else. I then told him that "When you don't tell me that you are having a friend over to our house, I feel uncomfortable and that you are hiding something from me. I want to believe you when you say that you are just friends, but hiding things make me doubt that."
He said that he could understand that and apologized. He also said that he would let me know in the future.
Did I totally screw it up? It was my first time setting a boundary since this all started.
E
M 46 / H 43 T 24/M 18 S 4 11/6/2014 ILYBNILWY 1/16/2015 Living in separate bedroom 1/8/2016 H moved out