I know you're waiting on that other shoe (you're not alone there), and it's tough.
When I find myself going there, I look at all the positives (ok, maybe not so many in my case, but they are there). I do this so that I'm not telgraphing to him the negative stuff that comew with waiting for the shoe to drop.
The tea was a good move. If he's bored, is there something he or you both like to do that might get you out of the house once ot twice a week? Maybe dancing? Even if he finds something that suits him then maybe he more positive when he's home.
Do you guys like to read? Reading to each other or even just the same books and talking about them...
His reaction to the note is interesting. In the past what kinds of things have you given him notes about? Did it tend to be negative stuff that you would have had difficulty talking to him about? Or maybe lovey dovey stuff? Either way, it might give you a clue to his reaction.
