In fall 2008, Michelle's fear of being dirty became all consuming and she plunged into depression.
"I became suicidal because I couldn't touch anything, and when you can't really touch anything, you can't do anything. You can't enjoy anything, so there wasn't really a point in living anymore," Michelle said.
Michelle worked with Weg in extensive therapy to manage her OCD. Outside Weg's office, Diane LeClair became her daughter's OCD coach, coaxing Michelle to get back to school one class at a time.
Parents such as LeClair invest a lot of time and money in treatment. Therapy for OCD is expensive, and insurance often does not cover the costs, leaving many families on their own.
Just ask John and Margaret Decorso, whose son Rocco was diagnosed with OCD and Tourette's -- two conditions that often are closely linked -- when he was 8 years old.
Fear of "what if" consumed Rocco, from the fear of getting sick to the fear of what could happen when he left for school. Every day, he begged his mother to repeat herself, to keep reassuring him that everything would be OK, which can tear down even the most loving moms.
"Sometimes we're like, 'Get over it, knock it off already!' said his mother, Margaret.
Signs that something was wrong came when Rocco was 5 years old, and he talked about wanting to die.
"He says, 'I can't live like this no more,'" Rocco's father John said, holding back tears. "Coming from a 6-year-old saying, 'I can't live like this. I want to live with God,' you know., 'Don't worry, Mom and Dad, I'll look down after you.' That's tough."
After seeing doctor after doctor, they eventually found Weg, who was able to offer treatment options for the struggling family.
OCD is a chronic disorder that lives inside people forever. Though there's no cure, but Weg said it can be silenced if you know how to manage it.
"We don't use the word 'cure' for OCD, 'cause that implies that you have OCD and then you end up not having OCD -- and, for the most part, that's not really the case," he told ABC News. "The vast majority of people that I work with end up being able to manage their OCD to the point that they're aware of it to a certain degree every single day."