He is right, he came back to soon. You already knew that though.
Be compassionate and understanding, let him know he is not trapped -- he will not be the bad guy if he chooses to leave, he is allowed to try and change his mind, and DO NOT try to fix it for him.
If you can't deal with the limbo, then don't. Leave the limbo. But don't try to force him to a place out of limbo because you don't like where he is.
