“Friends” is arguably one of the best comedy series to ever grace the TV. The show ran for 10 seasons before it came to an end in 2004. But fans were thrilled when the original cast came back for its reunion special. Everyone was there—Jennifer Aniston (Rachel Green), Courteney Cox (Monica Geller), Matthew Perry (Chandler Bing), Lisa Kudrow (Phoebe Buffay), Matt LeBlanc (Joey Tribbiani) and Davis Schwimmer (Ross Geller).

However, some of the cast had it harder than others. For example, apparently Anniston was having a tough time during the reunion—so much so that she actually had to leave the set and come back several times.

So what was it plaguing her so much about being there? Well, as much as the show was a hit, it wasn’t filmed during the best times in Anniston’s life. In fact, she was reminded heavily of the time she and her ex-husband Brad Pitt had split. The two had parted ways just a year after the show had ended, and being there was reminding her of what she called the “hardest time” in her life.

“Time travel is hard,” Aniston said in an interview with Hollywood Reporter. “I think we were just so naive walking into it, thinking, ‘How fun is this going to be? They’re putting the sets back together, exactly as they were’. Then you get there and it’s like, ‘Oh right, I hadn’t thought about what was going on the last time I was actually here’.”

Anniston didn’t expect it to hit so hard. In fact, she was kind of surprised at the flood of negative emotions that flooded her.

“It just took me by surprise because it was like, ‘Hi, past, remember me? Remember how that sucked? You thought everything was in front of you and life was going to be just gorgeous and then you went through maybe the hardest time in your life?’,” she said.

Sure, times were tough, and it even affected her to the present day by having to walk out of the set—but she also wouldn’t change what happened back then. It made her who she is today.

“But again, everything’s a blessing if you’re able to look at life’s ups and downs in that way. And if it all hadn’t happened, I would not be sitting here the woman that I am,” Aniston said.

To hear more of her feelings on set, check out the interview below!

Did you know Anniston was upset at all during the reunion?