Much of Hamlet is about the precise kind of slippage the mourner experiences: the difference between being and seeming, the uncertainty about how the inner translates into the outer, the sense that one is expected to perform grief palatably. (If you don't seem sad, people worry; but if you are grief-stricken, people flinch away from your pain.)
Once a book falls into our possession, it is ours, the same way children lay their claim: 'That's my book.' As if it were organically part of them. That must be why we have so much trouble returning borrowed books. It's not exactly theft (of course not, we're not thieves, what are you implying?); it's simply a slippage in ownership or, better still, a transfer of substance. That which belonged to someone else becomes mine when I look at it. And if I like what I read, naturally I'll have difficulty giving it back.
Try telling the boy who's just had his girlfriend's name cut into his arm that there's slippage between the signifier and the signified. Or better yet explain to the girl who watched in the mirror as the tattoo artist stitched the word for her father's name (on earth as in heaven) across her back that words aren't made of flesh and blood, that they don't bite the skin. Language is the animal we've trained to pick up the scent of meaning. It's why when the boy hears his father yelling at the door he sends the dog that he's kept hungry, that he's kicked, then loved, to attack the man, to show him that every word has a consequence, that language, when used right, hurts.
In its severe forms, depression paralyzes all of the otherwise vital forces that make us human, leaving instead a bleak, despairing, desperate, and deadened state... Life is bloodless, pulseless, and yet present enough to allow a suffocating horror and pain. All bearings are lost; all things are dark and drained of feeling. The slippage into futility is first gradual, then utter. Thought, which is as pervasively affected by depression as mood, is morbid, confused, and stuporous. It is also vacillating, ruminative, indecisive, and self-castigating. The body is bone-weary; there is no will; nothing is that is not an effort, and nothing at all seems worth it. Sleep is fragmented, elusive, or all-consuming. Like an unstable, gas, an irritable exhaustion seeps into every crevice of thought and action.
Kay Redfield Jamison