Camila Mendes, Lili Reinhart and Madelaine Petch "bonded" more after their relationships ended.
The 'Riverdale' stars relied on one another amid the coronavirus pandemic last year, particularly because they were going through a difficult time after Camila had split from Charles Melton in autumn 2019, Madelaine split from Travis Mills in February 2020 and Lili and Cole Sprouse ended their three-year romance a few months later.
Camila - whose one-year romance with photographer Grayson Vaughan ended in February - told Paper magazine: "We all got out of relationships at the same time and then went through this pandemic together.
"And now we've been bonded by how much change has happened. Me, Madelaine and Lili, specifically, we've never been closer than we have this season."
"It's really nice to have them, to feel like I do have friendships here — meaningful ones."
The 26-year-old star is grateful for her friendships because it was "really hard" for them all shooting 'Riverdale' in Canada, and being unable to return to their Los Angeles homes due to the coronavirus pandemic.
She said: "This was the first few months of 'Riverdale' in the pandemic, being away from our family and not being able to leave.
"That was a really hard thing for all of us, because we're so used to having our little apartments here in Vancouver, but we go back and forth to L.A. whenever we can, because that's home for most of us. And now we're not allowed to do that."
The situation was so stressful, Camila found her hair had started to fall out.
She recalled: "I got out of the shower and had a full breakdown."
But making the programme itself has become much easier for Camila and her co-stars.
She said: "We've noticed that sometimes indie actors will come onto the set, and they don't know how to assimilate to that kind of pace and environment. It took time for all of us to adjust to that. But now I feel like I'm always ready."