To the horror of countless fans, the previews for 1,000-lb Sisters were grim.

We knew that Tammy Slaton was hospitalized just hours after finally making the courageous return to rehab.

It was only upon watching the episode that fans saw how serious things became ... but not all of the news was dire.

Tammy awoke from her medically induced coma, and her brother reported that she had lost 115 pounds in just a few weeks.

The Season Finale of 1,000-lb Sisters had viewers on the edges of their seats on Monday night.

After a lot of urging and a lot of dangerous behavior, including drinking and smoking, Tammy Slaton knew that she'd gone too far.

Constantly in pain and feeling unwell due to multiple health struggles, it was time for rehab.

Her loved ones praised her for making this courageous choice.

The sad truth is that massive weight loss through diet and exercise, though a requirement for weight loss surgery, is not easy.

It is quite literally torture on the body, and Tammy knew that it would in some ways make her feel worse -- for a while -- than she already did.

Just one day after checking into rehab, Tammy suffered a dramatic health crisis.

She was transported by ambulance to a hospital, and had stopped breathing, her lungs having collapsed.

It was truly dire, and Tammy's family was preparing for the very worst news after she was placed in a medically induced coma and put on a ventillator.

Then, Tammy awoke.

It was, of course, weeks before she could be discharged from the hospital and return to rehab.

When she did, Tammy set to work, and her overjoyed family could not be prouder of her.

"And we stayed four days or so up there. And then the last day we were there, she woke up," Tammy's brother recalled.

"And," Chris noted, "she kept telling us she loved us and wanted to go home."

"I'm happy, I'm relieved, I'm still sad. I'm just grateful," Amanda gushed.

"I'm just like, good looking out up there, you know. Thanks," Amanda stated.

We prayed for a miracle and God gave us one," she expressed.

"She's okay. She's still alive. She has her life," Amy affirmed.

It was Chris' turn again to deliver an update on his sister's well-being.

"So she's lost 100 -- I think she told me 115 lb in total in 30 days," he revealed.

"I'm overjoyed that's she's ready to get on this train," Chris shared, "and start rolling down the tracks."

Chris may have been approximating Tammy's weight loss, but that could mean that she reached 534 lbs in just over four weks.

If the plan remains to stay in rehab for eight months, she could see exceptional weight loss to come.

In fact, given that this was filmed last year, she could already be down another 50 to 100 pounds.

The weight loss is important if she wishes to take Dr. Smith up on his offer of weight loss surgery.

However, we should all note that Tammy's rate of weight loss is not sustainable in the long term.

The human body is masterful at retaining nutrients and energy, and will learn to make do with less and less fuel.

That, of course, is why diet and exercise -- though potentially wonderful for health -- is better for short-term weight loss.

Over long term, people's bodies will find a way to return to their previous weight, which is why most diets and lifestyle changes ultimately fail.

It is hoped that Tammy's surgical remedy, in contrast, will allow her to find a long-term balance that will prolong and improve her life.