Hiding behind a computer or a cell phone makes it easier for them to say what is on their minds. They don't want to see/deal with the emotions and how we react to their conversations if we are standing right there in front of them. They do not like confrontation and one way to avoid that is by electronic means.
HaWho, it's time to stop responding to his messages. Sure, take one once in a while, but it's time to try something new. He's living under the roof w/you and it's time for frat boy to come out of the dorm room and have a face to face conversation w/you.
Ciluzen has given you some good advice/suggestions...it's time to try something new.
He wants open communication, then give it to him. Come out of the dorm room and act like a man and talk to you face to face.
Sit quietly, the answers will reveal themselves when you least expect them to. The past is gone, the present is a gift and you need to focus on today, allow the future to reveal itself when it is ready.