With magic, Lyra opened the fridge, whipped out a cold bottle of soda, and held it to her forehead. "Taaaaaaaaake me away, carbonation..."
"Lyraaaaa..." Bon Bon stood angrily in the kitchen doorway, glaring at her. "You told me that you had gotten over your anxiety over insects and spiders."
"And I have!" Lyra sipped some Dr. Pony. "For the most part!" She sipped again. "Just... so long as I'm not looking at them!" A third... slower sip. "...or hearing them or thinking about them... or being forced to perform spontaneous musical performances about them at a five year old's foalday party." A beat. She belched hard.
Bon Bon huffed. "So... what is this, a relapse?" Her brow furrowed. "Or have you simply been lying to me every time you've claimed to be feeling better about the past?"
"It's been a year, Bon Bon." Lyra stifled another burp and looked over the soda bottle at her. "Shouldn't I be getting better?"
"We're ponies, Lyra. Not robots." Bon Bon shook her head. "You can't be expected to get better by any form of metric or scale. If you're still dealing with panic attacks, I want you... I need you to tell me!"
"Yes... yes... I get it," Lyra groaned.
"Next thing we know, you'll be hallucinating changelings in public again."
Lyra's muzzle instantly scrunched. She tried pivoting to face the other end of the kitchen...
...but it was too late. Bon Bon saw it. "Lyraaaa... what happened?"
"N-nothing! I... uh... I ditched the foalday party, wandered around, caught a pegasus carriage home..."
"You didn't... see anything out of the ordinary, did you?"
"Pffft... it's Canterlot, Bon Bon. Not the Royal National Convention."
"No delusional visions of changelings or other hallucinations?"
"For crying out loud! No!" Lyra frowned. "I did not envision a changeling staring at me from across the train station—" She immediately winced.
"Oh Goddess..." Bon Bon face-hoofed. "...why don't I just put a bell on you and come running everytime it jingles?"
"Look, it's no big deal!" Lyra's voice cracked. "Didn't we agree on this before?"
"No, Lyra." Bon Bon stepped towards her. "What we agreed on before was that you were hallucinating the presence of changelings in random locations. But we didn't come to that understanding easily." Her blue eyes narrowed. "You fought tooth and hoof to try and convince me that the changelings you saw were real."
"Isn't that the sort of sensation somepony gets when they witness something 'real?'"
"So now you're saying that you're convinced a real changeling looked at you at the train station today?"
"I-I'm just saying it felt as real as the one I saw at the wedding!"
"Celestia on a bike, Lyra!" Bon Bon held a hoof over her chest. "I'm surprised you're not in the Canterlot Hospital tonight! Wearing a strait jacket!"
"Oh please..." Lyra rolled her eyes and chugged more of the Dr. Pony. "Mrmmmff... urp... you make it sound way worse than it really is."
"What can possibly be worse than hallucinating monstrous ponies constantly stalking you!"
"Let's flip the mirror around for a bit!" Lyra smiled crookedly. "Just for humor's sake!" She gestured. "What if every changeling I've spotted since the Canterlot Wedding has been real?"
"I'd be hating myself super hard," Bon Bon droned. "For shirking my duties as a professional monster hunter."
"Boy wouldn't that plunk a feather in your porridge!"
"But all of my devices, senses, and experience for tracking down changelings hasn't alerted me to their presence even once!"
"Isn't that sort of the point?" Lyra squinted. "I mean... they're changelings..."
"They're a bunch of creepy punks who got lucky once in our age, Lyra," Bon Bon said. "Since then, Celestia and Luna have utilized special magical leylines all across Equestria to detect their presence within a micrometer of accuracy!"
"Yeah? Well, if that's true, then how come you still keep a bunch of fancy changeling-detecting gadgetry underground somewhere?" Lyra waved a hoof. "What do you call it again—the 'Sweaty Hole?'
Bon Bon frowned. "It takes more than dependence on alicorns to be constantly vigilant—yes. I agree. But I've been watchful over you and Ponyville for over a year, Lyra. If there was a changeling presence here in this town—or anywhere in Equestria, for that matter—I swear to you that I would know about it! And if not me, than my friends would!"
"Yeah? And what if you and your friends are wrong, B-Squared?" Lyra's eyes narrowed. "What guarantee do any of us have then?"
"Lyra..." Bon Bon sighed, folding her forelimbs. "What is a more realistic and simple scenario?" She clenched her jaws. "That Queen Chrysalis has been sending spies out at random to hang out among the equine populace—invisible to everypony but completely insectoid in appearance to you and you alone... or that you've simply been recognizing benign patterns as signs of changeling presence due to the personal trauma that you've experienced?"
"Uhhhhhh..." Lyra gulped. "...could it be both?"
"Alright, then. Let's say that this is something that really happened! There you were at the Canterlot train depot! Completely minding your own business! When—lo and behold—a changeling showed up! Stared at you! Gawked at you!" Bon Bon cocked her head to the side. "What would a sane pony do when confronted with such an obvious threat to her and those around her?"
"I... uh..." Lyra gulped, sweating suddenly. "I-I guess I would tell somepony about it. Loudly—to get their attention—if need be."
"And did you do this?"
Lyra bit her lip. Ultimately, she hung her head. "No."
"And why not?"
Lyra sighed out the side of her muzzle. Her bottle of Dr. Pony hung half-empty in her grip.
Bon Bon leaned forward. "Perhaps... it's because you know... deep down inside... that you have a problem, Lyra? A problem that needs fixing?"
"Yeah... well..." Lyra muttered, frowning. "These Stinkenfarter visits ain't gonna help that."
"And how do you know that?!" Bon Bon flung a hoof through the air. "What logical, rational explanation do you have to prove that regular therapy won't help you confront these issues and more healthily process them?!"
"Because I'm... n-not a total nutcase like Minuette or Twinkleshine!" Lyra exclaimed, her voice rising to match Bon Bon's. "I have crud that I need to get done! It's hard enough as it is getting noticed as a musician in Equestria! I d-don't need all of this... psychiatry crap holding me back!"
"Oh yeah?" Bon Bon glared. "Because you're not exactly doing a bang-up job at the pace you've chosen!"
"Because I keep having to juggle all of this stuff that you and Lemon Hearts are burdening me with!"
"You mean you keep having to lie to us like we're the opposite of your friends!"
"Bon Bon, friends don't treat other friends like broken wagon wheels! Have a little faith in me!"
"I do have faith in you, Lyra!" Bon Bon shouted. "I've had so much faith in you that I hardly even remember what my old life was like! And if you feel like I've treated you like a broken object—I apologize! But I've done everything that I've done—each and every day that I've done it—to protect you! Don't you realize that, Lyra?! Don't you understand that... that I want the best for you?! That I want you to be safe?!"
"But Bon Bon..." Lyra moaned. "Being 'safe' kills me!"
Bon Bon opened her muzzle. Her ears drooped and her coat paled slightly. Then... fighting back a foalish tremor like the young daughter she once was, she eventually muttered in a low voice: "I'm sorry you feel that way, Lyra. Really, I am. But if being safe kills you... then being endangered will bury you. Believe me. There're are worse things in Equestria... way worse things than hallucinations or a stumbling music career."
Lyra bit her lip, avoiding Bon Bon's gaze... shaking slightly.
Bon Bon took a deep breath. "Lemon Hearts says that she and her friends will be going on a vacation to Appleloosa to attend special therapy sessions out in the desert. It's promising to be a relaxing, tranquil experience... and it can only do a mare like you some good. They'll be here in Ponyville to catch the next train south in about seven days." She took a bold step forward, eyes narrow. "I want you going with them on that trip, Lyra. It will be good for you... it will be good for your friends... and it will be good for us." She gulped. "If you care even the slightest bit about our friendship... or the lengths that I've gone to help you get to where you want to be... then you will do us both a favor and be on that train to Appleloosa in a week. And I don't mean just to humor Lemon Hearts and then split off for parts unknown... but an honest-to-Goddess commitment to something that is healthy... something that is right." She took a shuddering breath. "Can you promise to do that for me?"
Lyra stood in place, looking off. She said nothing.
Bon Bon fumed. "Got nothing to say?" Her ears folded back. "Fine. Be silent." She stormed off across the apartment. "Goddess forbid an aspiring musician should be creative and on point for a change."
With thudding hoofsteps, she scaled the staircase, entered her bedroom, and slammed the door shut.
Lyra's eyelids lowered. With a dull sigh, she placed her bottle of soda on the kitchen counter and leaned limply against the nearby wall in dead silence.
Upstairs, in Bon Bon's room...
The mare slumped against the door, panting. She grimaced... her ears echoing with her own words. At last, her strength gave out, and Bon Bon slid down to the floor. She buried her muzzle into her forelimbs and quietly... delicately cried...