Libby, Sounds like his depression is lifting just a bit at a time. Communication is difficult for them and it will take time for him to talk more freely.
I think you are very wise in allowing him to have his space and time w/no pressure from you. Continue doing what you are doing and keep your expectations at zero.
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.
