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(CNN) -- At age 13, Hope Witsell struggled in middle school. Not because her class work at Shields Middle School in Ruskin, Florida, was challenging, but because Hope was being bullied.

Her friend, Kyla Stich, told CNN that fellow students would "walk up to her and call her 'slut,' 'whore,' and they would sometimes, they would call her 'skank' and just be really cruel to her."

Another friend, Lexi Leber, said, "We had to make like a wall, we had people surrounding her, and she had to be in the middle because people would come by and try to hit her and push her into a locker or something.

"She was afraid to walk alone, she was afraid someone would do something to her, like verbally attack her, so she would always have someone with her," Leber added.

This all started in the spring of 2009 during the last week of school.

Friends and family say Hope had "sexted" a picture of her breasts to her boyfriend. Another girl from school, they say, got her hands on the photo and sent it to students at six different schools in the area.

Before Hope could do anything to stop it, that photo had gone viral.

The school alerted Hope's parents. Her mother, Donna Witsell, told CNN how she learned about the photo.

"The assistant principal had a meeting with my husband and I and pretty much told us that he did not see the image but that he had heard that it was Hope and when he confronted Hope, Hope did not deny it. She wasn't proud of it but she didn't lie," Hope's mother said.

Mrs. Witsell says she had warned her daughter about the dark side of technology, about "some of the pretty sexual images of young girls and guys."

She added, "Hope was very aware of that, of inappropriate dress and most definitely posing."

Still, because of that photo, Hope had become a target for 11-, 12-, and 13-year-old bullies.

But she didn't share her pain with her parents.

Even when bullies wrote horrible things about Hope on a MySpace page called the "Shields Middle School Burn Book" and started a "Hope Hater Page," the young girl kept silent.

Summer provided a bit of a break, but when the new school year began, the taunting was even worse.

On Saturday, September 12, 2009, Hope Witsell helped her father mow the lawn. They cooked a special seafood dinner together as a family. Then Hope disappeared to her room upstairs. Her parents stayed downstairs and watched TV.

Donna Witsell will never forget the moment she went to say goodnight to her daughter.

"I went upstairs to go in her room and kiss her goodnight. That was when I found her. I screamed for my husband. And started doing CPR."

It was too late. Hope was already dead. She had used her favorite scarves to hang herself from her canopy bed.

After Hope died, her mother learned her daughter had been summoned to meet with a school social worker. A spokesperson for the school says the social worker was concerned Hope might have been trying to hurt herself, so she had Hope sign what's called a "no harm" contract in which Hope agreed to talk to an adult if she wanted to harm herself.

Hope's mother says she was never told about the contract, which she found crumpled up in the garbage in her daughter's bedroom after she died.

School officials told CNN they believed the social worker had tried calling Hope's mother to alert her but weren't sure if she had left a message.

"The school dropped the ball," Donna Witsell said.

"The school did not call. We have the digital telephone; we have the cell phones that indicate when there was an incoming call and what number was calling in. We have a house phone, I have a cell phone, my husband has a cell phone. We have emergency contact numbers at the school which was my sister-in-law and her husband. There was no indication that the school called any of those numbers," Hope's mother said.

Days after Hope died, her older sister, Samantha Beattie, discovered the bullying was still going on. Even in death, Hope could not escape it.

"I knew she had MySpace and Facebook. There were people putting comments on there: 'Did Hope really kill herself?' 'I can't believe that whore did that.' Just obscene things that I would never expect from a 12-year-old or a 13-year-old," said Samantha.

In the year or so that has passed since Hope Witsell took her own life, her mother has started a group called Hope's Warriors. She hopes it will help combat bullying and save other moms from feeling the horrendous pain that she feels.

Donna Witsell has a message for parents: "It happened to my daughter, it can happen to yours too. No one is untouchable. No one is untouchable."

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