When asked about Stewart's cheating scandal, Nicks told Us Weekly that folks need to give Stewart a break.
"I was her age once, and exactly what happened to her happened to me two or three times, and whoever it was that I was with forgave me all two or three times," said the Fleetwood Mac frontwoman.
"The fact is that when you're young and you've been in a relationship for a long time and something comes along that is a little bit overwhelming and magical, and you're kind of in another situation with someone else … things happen," Nicks said.
Nicks' recent single, "Secret Love," is about a similar situation.
"It's definitely about something that was not to be and not to be talked about," the singer told ABCNews.com last year. "He must have been in a relationship. And I must have cared about that and didn't want to destroy his life or I wasn't fighting hard enough for it. I think I walked away from the relationship for that reason. It was just over and not to be."
Twi-hard Nicks is friends with both Stewart and Pattinson and even penned a "Twilight" inspired song for her latest album, "In Your Dreams."
She said if Pattinson is willing to forgive Stewart for her mistake, then so should everyone else.
"If what they have is that special [that] they can overcome it, then good for [them]," she told Us.
Nicks hits the road with Fleetwood Mac next April. Tickets go on sale Dec. 14.