Doherty, whose own personal life has often been on public display, said she sympathizes with Garth.
"I think that for somebody like Jennie who values family so much, this is incredibly hard for her," Doherty told People Thursday.
Doherty made the comment during a call promoting her new reality show, "Shannen Says".
"I feel for her and, more importantly, I feel for her kids," Doherty said. "There are children involved [and] children have access to the Internet and everything that somebody may write."
Garth has her own reality show, "Jennie Garth: Little Bit Country," premiering April 20, following her and her three daughters as they move from LA to a simpler life in California's Santa Ynez Valley.
Doherty, who was known as a hellion in her younger years, said her friendship with Garth has strengthened as time has gone by.
"I did the new 90210 with Jennie and there was something very different about our friendship," Doherty said. "We were able to look at each other as grown women and really acknowledge that we like who the other person was now, as adults."
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