Looking forward, it'll be interesting to see how Joey's visit to see Jack goes. I know Jack had also been seriously mislead by Shaun but he did say
"Joey, promise me! If there is any future for us, then I don't want to have it hanging over me that I was the cause of your friendship breaking up, and I also don't want to get into anything if Shaun is going to be avoiding us because we are together, I happen to like the guy."
Jack isn't aware of Shaun's current mental state, but I'm not sure what happened at Shaun's house was what he had in mind? The way Joey & Jack "resolve" this will be telling for their future relationship.
I can't hate Shaun he needs some serious help, and I can't see him getting it from his parents. A desperate situation for him, let's hope he doesn't take any reckless steps.