Nothing ever bothers you. the headaches you get when someone is annoying, and the satisfaction you get when you think about hurting them
I infer that it hints to that the man does not do labor work. He does not exercise, and can be spoiled. Just try to put yourself in his shoes- what made you to be this way, why are you like this, and how are you like (what do you like, etc.). I do not know if this is right, just a guess.
The note says "I love you." They have to be so secretive because the Party did not approve of them starting any kind of an affair like the one they were going to have.