In my view...the card is unnecessary. YOU are going to MC, that right there shows your are remorseful for your actions and you are working on correcting them. Doing too much stuff (like a card to thank him) right now...can be going overboard and make you appear needy, that can be translated in to "unattractive" KWIM? Just go to the MC, and validate him while you are there....and validate him outside of MC too, but don't go overboard.
