Once again, David Muir, as "20/20" continues. Reporter: 15-year-old Bridget sits in the waiting room two seats apart from her mother. Her obsessive compulsive disorder, her fear of contamination,... See More
Once again, David Muir, as "20/20" continues. Reporter: 15-year-old Bridget sits in the waiting room two seats apart from her mother. Her obsessive compulsive disorder, her fear of contamination, prevents her from sitting any closer. You'll remember the last time they worked the entire time on simply sitting on the same couch. No. Don't. Don't. Okay. Reporter: Karen has not been able to hug her own daughter for months now. And it is Bridget who's in the driver's seat. It is a painstaking process every time. It's taken seven full therapy sessions just to get this far down the couch. Her mother slowly moving her body closer. All is going well until her mother reaches for her purse to pay the therapist.xd No, it's too close. Get it away. Reporter: Bridget is afraid getting close to that purse will contaminate her. Bridget tells the doctor she is done. And outside, she shows us how even leaving together is not easy. Now, she has to come out and I close the door. Because if she touches the door, then I can't touch the door anymore.u! Reporter: All of this is irrational, and Bridget, like S! Many children with OCD, knows that, but she's still afraid that her mother and the rest of her family at home is contaminated. And Bridget refuses to go there. Her mother is about to drive her nearly an hour away back to her ?? grandmother's. Remember, that is where Bridget is now living instead. I can't put my feet or my shoes on the ground, so I take them off and then put them on top, and then I sit sideways. Reporter: For Bridget, everything is complicated, even the simplest of things, like getting into the car. She takes off her shoes, because they can't touch the floor of the family car.e1 So I can't be too close to her. Before, I used to have to sit on my feet and they would become numb. Reporter: While inside another car, another mother and daughter in their own relentless fight against OCD. What are you trying to tell your OCD? To get lost. Okay. Reporter: 14-year-old Michelle Leclair, who hasn't been able to step inside her school for four months now. Her mother, Diane, had to quit her job as a teacher to work full-time helping Michelle fight her OCD. When she was going to school,!u?? she would cry for an hour and a half every night, saying how difficult it was to go to school, but I couldn't touch her. Reporter: Michelle's OCD also involves contamination, but her fear is different. Her family is fine. It's the kids at school she's afraid of, afraid they're dirty.r she can't go to school or anywhere in public where she has seen the other students. We had to go, like, hours away just to go get, like, a pair of pants or get cleaning supplies because everything around here was contaminated. All the stores were, because the kids from school had been there. Reporter: It is a crippling fear that has left her isolated at home. Her laundry has to be done separately from the rest of the family. And one laundry cycle often isn't enough to convince Michelle her clothes are clean. Even the washer has to be washed. She showers incessantly at home, blistering hot water. At one point, her parents couldn't even get her out of the shower, not even when there was a brand new puppy waiting for her. We were gonna go get him puppy toys and take him to the store and she was so excited that whole day. And after an hour in the shower, I'm like, "We need to leave if you want to go," and she couldn't do it. I pulled her out of the shower, and she just sat on the floor, rocked and cried.0& Reporter: Her OCD taking over her life. Doctors say, with children who have OCD, Michelle plunged into depression. I became suicidal because I couldn't touch anything. You can't enjoy anything. So there wasn't really a point in living anymore. Reporter: A far different portrait from the little girl who was once a straight "A" student, a dancer, who loved dressing up, a child who once proudly displayed her smile. Your school situation will be -- Reporter: When we first met up with her, she'd already begun therapy with Dr. Weg. And now, she and her mother are taking the next step on their own, actually practicing going to school when the halls are empty. And they're headed to their first stop, the locker room. My heart is beating much faster now. And then, so I touch the doorframe and then do the door handle. Reporter: The doctor has told Michelle to touch what she's afraid of, what's dirty, and then to touch her own skin to prove that there's nothing to be afraid of. The doctor has told her to keep track of her anxiety on a scale of 1 to 10. Like a seven. Touch the walls because you're not touching anything. You're taking little baby steps. Michelle, you're not touching the walls. Touch your hands, your arms, your face. I'm contaminating myself so that no part of me is considered, like, clean. Right now, if you could do anything in the world, what would you be going to do? Leave. Take a shower. Reporter: With the locker room now barely conquered, the next battleground, gym class. It's been five months since she stepped foot inside the gym. Can you go over and touch the basketball? Do you want to hit me? Yeah. Now, you know kids touched that, right? What does it feel like? I think the germs are, like, coming into me and, like, going through my blood. Reporter: Her full-time coach, her mother, taking careful note of her progress. I'm very proud of what you did. You touched the walls, you sat on the, the bench. Reporter: A proud mother and her daughter leaving school after their own sort of gym practice. While back in the therapist's office, Bridget is about to take a huge step too. It's been eight hours of intense therapy with Dr. Weg, and she still has not allowed her mother to touch her. It's been months since mother and daughter have hugged. All right. That's pretty good. Reporter: Bridget and her mother grasp a small wand between them. This is huge. Bridget? Find your center. Show her who's boss. Do it, do it, do it, do it. Just stay with it. Just hold on. Reporter: This is the first time Bridget has touched her mother in four months. I need your fingers. All of my fingers? Yes. There it is. That feels really good. No, it doesn't. It's very difficult for parents to come in and not believe that they've done something wrong, that their kid has all these fears and, and strange and bizarre fears. What did I do wrong? Reporter: Once her fear subsides, the doctor pushes Bridget to hold that hand again. Let's have the hand back. Good for you, good for you. Okay. Reporter: And as we were about to learn, Bridget's OCD fight is far from over. What was it that led to this? No.
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