"When she said, 'I don't want to see you anymore,' life became miserable," the source said.
According to police, Hart harassed von Tiehl by electronically disrupting her bank, phone and utility services.
He has been charged with identity theft, disruption of service, harassment and possessing instruments of a crime, court records show.
In 2003, Hart pleaded no contest to several counts of stalking and threatening his ex-girlfriend. He was sentenced to time served and probation on those charges.
Three weeks after that sentencing, Hart was arrested on charges of harassing his new girlfriend, court records said.
While in jail on those charges, he was hit with two warrants for violating his probation on the previous case by calling the victim at home, court records show.
Even though a jury acquitted Hart of all charges in the second case, he was sentenced to state prison for violating the terms of his probation in the first case.
A source said Hart served a year in state prison and then six months in a halfway house before being released in August 2010.
Police believe that Hart has harassed other women.
One source said he has open warrants out of Baltimore and open cases in Cherry Hill for similar stalking charges.
Local police believe there could be more victims in the Philadelphia areal.
"They're all ex-girlfriends," one source said. "He can't take no for an answer."
Through CBS 3 spokeswoman Joanne Calabria, von Tiehl declined to comment on the case.
"This is a personal matter that is now being handled by the appropriate law-enforcement agencies," Calabria said. "We have no further comment, but, of course, Erika has our support through this process."