About the email, h was probably embarassed... Let him slide on this, and you keep from checking up on him... Let him have some dignity...
Let him know all you want is honesty... Reassure him that he can tell you the truth... Let him be able to trust that you aint gonna go off, and double check on him...
SB he created the serious offense, however in his eyes he needs to trust you too...
You did ok for the most part... Just develope a new game plan... Like maybe just sit in the puter room doing something else not paying full attention to h next time he goes online...