Fiona Apple takes time off to tend to ailing pooch

We warned you to steel yourself before reading Fiona Apple's explanation for postponing her South American tour, because the singer/songwriter has written a letter that could touch even the cynical.

On her Facebook page, Apple said she couldn't set out on a string of dates - which were reportedly set to start in Brazil next week - because her 14-year-old Pit Bull Janet is dying.

"Here's the thing ... [Janet's] been ill for almost two years now, as a tumor has been idling in her chest," Apple writes. "I got her when she was 4 months old. I was 21 then, an adult officially - and she was my child. ... Janet has been the most consistent relationship of my adult life, and that is just a fact."

Apple recounts how she found Janet, who suffers from Addison's Disease, in Echo Park with a rope around her neck and covered in bite marks. Since then, Janet's become "my best friend and my mother and my daughter, my benefactor," Apple says. "[S]he's the one who taught me what love is."

When Apple returned from the last leg of her U.S. tour, she noticed Janet had taken a bad turn for the worse, not even wanting to be walked.

"I can't come to South America. Not now," the musician told her fans. "I know that she is coming close to [the] point where she will stop being a dog, and instead, be part of everything. She'll be in the wind, and in the soil, and the snow, and in me, wherever I go. I just can't leave her now, please understand. If I go away again, I'm afraid she'll die and I won't have the honor of singing her to sleep, of escorting her out."

While postponing a tour is never easy for an artist or the fans who were planning to see a performance, Apple's confident she made the right choice.

"Sometimes it takes me 20 minutes to pick which socks to wear to bed. But this decision is instant," she writes. "These are the choices we make, which define us. I will not be the woman who puts her career ahead of love and friendship."