The Dementors swooped towards them in an ominous rustle of black cloaks. Coldness began to seep into Harry’s veins, the ghastly pull of nothingness enveloping him with its icy embrace.
He thrust out his wand with conviction, focusing on his happiest memory, let it fill him to bursting. “Expecto Patronum!”
His wand fizzled pathetically. He tried it again, but it was no use; no white galloping stag emerged to drive the darkness away.
Harry shot a rather panicked glance at Snape. “It’s not working! Why is it not working?”
“Isn’t it obvious?” Snape snapped at him. “The metaphor has collapsed, Potter!”
The... “What?” Harry asked in stunned incomprehension, feeling colder and colder by the second.
“The metaphorical representation of depression that Dementors signify, Potter,” Snape hissed impatiently. “The author stretched it to breaking point, and failed to acknowledge that unfortunately, a single happy memory is unlikely to do very much in the face of considerable mental health problems. Repeated exposure to this trope has broken the frankly laughable remedy to the problem at hand.” He sighed heavily. “I knew this was bound to happen, eventually.”
Harry hadn’t really understood a word of that, but it wasn’t important. “Great, your predictions of disaster were accurate as ever, but how do we fix it?”
Snape’s expression flickered rapidly across a spectrum of outrage, frank fear and resignation to settle eventually on utter disgust. “Quick,” he ground out, “talk to me about your feelings!”
Harry stared at him blankly.
“Your feelings, now!” Snape shouted, with an impressive glare. “Everything bad that has ever happened to you. It is the only solution!”
“Well...” Harry began tentatively, but quickly picking up speed as he saw how close the Dementors had got, “The Dursleys were horrible to me, all the time. They treated me like shit, frankly, and I felt like nothing, when I was with them, as if it wasn’t horrendous enough that my parents were killed by a dark wizard...”
“Go on,” Snape encouraged, and began to run on the spot.
“And the whole being the Boy Who Lived shebang really ain’t all that, either. I always feel so cut off, so lonely, and nobody can ever understand. Why are you doing that?”
“Exercise increases the release of endorphins. It has been demonstrated in clinical trials that it aids mild to moderate depression. Keep going, how does that make you feel?” He looked immensely pained at these last words.
“Like shit,” Harry said, beginning to run on the spot himself. “And then I thought Sirius was going to give me the home I always wanted, but first he needed to hide and then I had to go and get him killed, and it made me feel so... so...”
“Angry?” Snape suggested, digging through his robes.
“Yes,” Harry agreed readily. “Angry at everyone, and guilty, so guilty...”
Snape chucked something his way. Harry caught it and examined the small white pill with incomprehension.
“It’s a selective serotonin reuptake inhibitor,” Snape explained, still jogging as he swallowed one himself. “Front line treatment, though not terribly effective in isolation. I should warn you, there’s a small risk that it might lead to the Dementors swooping down on you instantly, but it can’t be helped. The scientific method is hardly magic, after all.”
That sounded mildly alarming, but Harry popped the pill anyway, for want of other options. “Cedric, I feel guilty about him too,” he volunteered. “And knowing that I have to kill Voldemort, Jesus, can you talk about pressure? It’s like everyone expects me to be this superman, but I’m just Harry and half the time I don’t know what the fuck I’m even doing.”
“You don’t say,” Snape commented acerbically. Harry decided to ignore that hugely unsupportive statement, casting a quick glance at the Dementors instead. It appeared to be working... maybe? They were hovering in the air, no longer approaching, except...
“They’re still coming for you!” Harry shouted with alarm. “You have to do it, too! Tell me about your feelings!”
“I can’t possibly,” Snape gasped out with something close to a moan. “Do you have any idea for how many years I’ve repressed the hell out of them? Has it not occurred to you that the only way I know to channel my pain is through anger? Most clinical psychologists would probably diagnose me with a personality disorder, and a treatment-resistant one at that!”
“But it’s the only way, right?” Harry confirmed. “I’m not letting you get Kissed - or at least not by them, come on, I know you can do it. You’ve faced so many horrible things, and you never let them get the better of you. You can’t give up now!”
Snape’s face twisted in a grimace of pain. “I suppose it has to be better than electroconvulsive therapy,” he conceded, before taking a deep breath. “My father,” he began, “was a horrible, abusive bastard...”
They ran on the spot, talking, for a very, very long time.