(NEW YORK) -- They are a mother and daughter who consider each other best friends. And yet, Bernadette and her 14-year-old daughter, Taylor, who asked that 20/20 not reveal their last names, don't eat meals together, don't share any activities and don't even speak to each other. It's all because everyday sounds Bernadette makes -- clearing her throat or sighing -- can send Taylor to the brink.
"It's like an almost undescribable amount of anger and, like, rage that I just can't control," Taylor told 20/20.
Taylor suffers from misophonia, a mysterious condition whose name literally means "hatred of sound." Misophonia makes it difficult to tolerate everyday noises such as chewing, coughing, even breathing. And while many might say they get annoyed at such sounds, for those with misophonia, the consequences of hearing such "trigger" noises are far worse than mere irritation: violence, isolation, depression and even thoughts of suicide.
Taylor has attempted suicide three times -- attempts, she said, were triggered by anti-depressants that did nothing to help her misophonia.
"I don't want her to give up, 'cause she's tried to give up," said Taylor's sister, Alex. "I just want her to keep moving."
Taylor's symptoms began when she was 8-years-old.
"I coughed, and she covered her ears, and she ran away," Bernadette said.
Eventually, it grew much worse.
"She's hit my head against the wall. She's kicked me. She's pushed me," Bernadette said, "just whatever she can [do] to stop the sound from coming from me. "
Once the rages pass, Bernadette said Taylor immediately feels remorse for her behavior. But the teen told 20/20 that when in the grips of such a rage triggered by an offending sound, that "sound will replay in my mind until I get the anger out ... until I somehow get out all my frustration."
Audiologist Marsha Johnson of the Oregon Tinnitus and Hyperacusis Treatment Center is one of the only experts who treats misophonia patients. Johnson said the cause of misophonia is suspected to be a "neurological glitch in a very low level of the brain."
Watch the full story on 20/20 Friday at 10 p.m. ET.
Copyright 2012 ABC News Radio