In 2004, not long after the birth of her third child, Amy Tenderich received a shocking news from her doctor. At age 37, she was diagnosed with type 1 diabetes — “the insulin-dependent kind, not the diet-and-pills-treated kind, which is known as type 2 and is 90 percent more commonly diagnosed among adults.”

She reacted as almost anyone might:

Suddenly my life became all about poking my finger for blood samples to monitor my fluctuating blood glucose levels a dozen times a day, injecting insulin at least six times a day, and constant worry about my diet, activity level and how all of this affected my glucose readings. If my blood sugar went too low, I might pass out. If it went too high, I’d feel listless and irritable and I’d be increasing my risk of serious “diabetes complications”—including blindness, kidney failure and leg amputation. I felt frightened and alone in ways I’ve never imagined before. Desperate for guidance, I was reduced to setting up coffee dates with friends of friends of friends who might know someone who has type 1 diabetes.

She turned to the Internet but was dismayed to find that online medical information back then was pitched primarily to medical professionals. She decided to use her experience as a writer for the high-tech industry to keep an online journal of her experiences, with the thought what she learned might be useful to other patients.

I called my site DiabetesMine.com — a play on words for “It’s mine, I’m stuck with it” and the notion of “a gold mine of straight talk and encouragement for people living with diabetes.”

And the people with diabetes came. They gave me great tips about coping with diabetes. Sometimes they argued with me. Often they said thank you for putting myself out there and helping them feel less alone. A few of them actually made me cry.

Tenderich says the editing her website has been an extremely valuable, educational experience:

First, I learned all sorts of facts about my own health that doctors never told me. I learned that thousands of other people out there have been diagnosed with type 1 diabetes later in life, like me — a condition called LADA (latent autoimmune diabetes in adults). From other patients I also learned essential basics about related conditions, like gluten intolerance (celiac disease), and Raynaud’s syndrome, a circulation disorder in the hands — both of which I suffer from, along with the diabetes.

Second, a whole community of “patient bloggers” has grown up around me — hundreds of other people sharing their health challenges on the Web. We exchange treatment and insurance tips, hold online chats, link to each other’s sites, and even manage to meet in person sometimes.

The site has been a statistical success too:

I soon discovered that my own little blog had upward of 50,000 readers each month, and comes up in the top three when you Google “diabetes blogs” — a search that thousands of surfers must be doing every single day,” writes Tenderich, “Now I find myself suddenly being approached by dozens of companies interested in my site. They either want me to review their products, have my Web site linked to theirs, or even offer me money to advertise — a direct channel for the 21 million Americans living with diabetes.

Tenderich adds that sites similar to MySpace or Facebook are in development now that will be geared to people living with specific illnesses, “from sleep apnea to diabetes to Lou Gehrig’s disease.”