While on The Ellen DeGeneres Show to celebrate Big Bang's upcoming series finale, Cuoco said she started crying "out of nowhere" when rehearsing a scene with Johnny Galecki and Parsons before the holidays.
"And the crew, all the camera guys and everyone came out and they were like, ‘We're so glad you cried, because we've been waiting to cry,'" Cuoco recalled. "And then they all gave us this huge group hug and we all just cried for like 10 minutes."
Parsons was the only who has not shed a tear over the show ending - yet.
"I haven't cried yet. I have a very deep fear—seriously—that the most unexpected thing is going to happen, I'm going to absolutely lose my s–," the actor said.
"Yeah, we're all scared of that," Cuoco chimed in.
"Because it really is profound, the amount of time of your life, and it's like more than, I think, any of us can get a grip on and I'm worried something is going to trigger me, like deep down, something is going to be like, ‘Oh! I didn't know that was there! That hurts,'" Parsons explained.
"If anyone hugs me about it, I just start crying," Cuoco said.
Parsons is one of the main reasons why the show was ending. CBS, Warner Bros. Television and executive producer Chuck Lorre chose to make Season 12 the show's last after Parsons said he would not be renewing his contract after this season. Parsons played Sheldon Cooper for all 12 seasons, earning a Golden Globe and four Emmys. The character is so popular that CBS' prequel series Young Sheldon, which Parsons narrates, is on its second season.
“It’s both as complex and as simple as just feeling innately that it was time," Parsons told Entertainment Weekly earlier this year. "It speaks to a lot of things, none of them bad. There is no negative reason to stop doing Big Bang. It felt like we have been able to do this for so many years now, it doesn’t feel like there is anything left on the table. Not that we couldn’t keep doing it, but it feels like we’ve chewed all the meat off this bone."
Parsons said he believed it felt like the "right time in my life" to move on to the next chapter of his career.
"It will be very, very sad when it does end, even knowing [I am] okay with it," Parsons told EW. "People are okay when they graduate but there are frequently tears at graduation. It’s hard to say goodbye to people that you have worked with for so long.”
The Big Bang Theory airs Thursdays at 8 p.m. ET on CBS.
Photo credit: Michael Yarish/Warner Bros. Entertainment Inc./CBS