Rebecca Sedwick Update: Boy reported to be at center of alleged bullying behind Fla. girl's suicide speaks out

John Borgen, above, who reportedly dated both Rebecca Sedwick and one of the teen girls accused of stalking her.
CBS affiliate WTSP

(CBS) LAKELAND, Fla. - Court documents allege one of the girls arrested in  the wake of the death of 12-year-old Rebecca Sedwick began harassing Rebecca over a boy both girls had dated. Now, that boy is speaking out, telling CBS affiliate WTSP that he never expected one of his former girlfriends to commit suicide and the other to wind up behind bars.

"It shocked me, it made me mad because she should have just told somebody," said John Borgen, the former boyfriend of both Florida girls.

According to WTSP, Borgen knew as many as 15 girls from his school were teaming up against Rebecca, but never expected her to be driven to commit suicide.

"They need to take life seriously," said Borgen. "Why do you need to be bullying somebody?"

On Sept. 9, authorities say, Rebecca climbed a tower at an abandoned concrete plant and hurled herself to her death.

Rebecca Sedwick
CBS affiliate WSTP

Authorities have said Rebecca was "terrorized" by as many as 15 girls who ganged up on her and picked on her for months through online message boards and texts. Polk County Sheriff Grady Judd said the bullying began over a "boyfriend issue."

Two girls, ages 12 and 14, were arrested Monday in connection with the case and charged with felony aggravated stalking, according to the Polk County Sheriff's Office. Judd said investigators made the arrest after the 14-year-old made an incriminating comment on social media over the weekend.

"She made a comment in reference to, 'Yeah I bullied Rebecca, and yeah she's dead, but I don't give a blank,'" Judd told CBS News.

Judd said parents should be aware of what their children are doing and has not ruled out charging the young suspects' parents.

WTSP reportedly spoke to the father of the 12-year-old suspect who said "there's two sides to every story."

After losing a daughter himself years ago, he says his whole family is devastated over what happened to Rebecca, reports the station.

Complete coverage of the Rebecca Ann Sedwick case on Crimesider