I would leave a note thanking him for looking after the pets and wish him a nice Christmas. Nothing more than that. Look at him as a house and pet sitter. Wouldn't you wish them a nice and/or Merry Christmas?

Enjoy your time away and leave the MLC at the door for a few days.

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.