TLC's "My 600-lb Life" is depressing in the best of episodes. Each week doctors work to save morbidly obese people from themselves. Even successful weight loss stories are tinged with pathos. The fails are heart-breaking. Take Penny from season two --Dr. Nowzaradan was worried that she wasn't motivated and sure enough, after gastric bypass, Penny only lost 35 pounds. But the bittersweet news is that everyone can learn from stories of weight loss failure. Here's why Penny didn't lose weight and take-aways on trimming the fat.

You get what you put into surgery

It's not that Penny cannot lose weight. She will not. She's in denial. She says weight doesn't matter. She purposely moved away from her doctor's care shortly after surgery, symbolically cutting the lifeline. She uses her extreme couponing to justify buying junk food. Because she wasn't willing to put anything into the gastric bypass, she only lost 35 pounds. A lot of people think weight loss surgery is a magic bullet that will enable them to lose weight without making any sacrifices. But surgery pays out what you're willing to invest in it. Now Penny says she wants surgery to remove excess skin. That's the kind of surgery you get to tie up loose ends after you lose a lot of weight.

Skin isn't Penny's problem -- it's fat.

Enabling family puts kibosh on weight loss

In most all cases, obesity stems from addiction to food. An alcoholic must want to quit and an obese person has to desire weight loss so bad she can taste it. Zsalynn Whitmore of "My 600-lb Life" did and look at her miraculous transformation. At 538 pounds, Penny was -- like most obese folk, bedridden.

She wanted to be there for her son but not bad enough to break bad habits. She was (and still is) dependent on her family for care. But she didn't start life that way. Because she didn't exercise when she could, now she can't. Now her family "must" care for her because she "can't" But can she? Yes. "Can't" usually translates to "won't." Eating isn't an automatic response.

Every person controls every bite they put in their mouths. If you want to lose weight, whether you have 15 or 450 pounds to shed, you can do it if you will it. Help is available. Weight loss supplements like white kidney bean curb cravings. Family support is important too -- not support as in enabling, but empowering. As soon as Penny's husband stops buyingthe junk food and stops helping her stay obese, Penny will lose. She will have no choice.