"I went over to see Charlie and Charlie was just getting ready to leave," Nassif said. "Charlie was feeling a lot better when I took him home."
On Wednesday, Sheen put out a written statement -- his first public comment since his hospitalization. He thanked fans, co-stars and CBS -- especially Les Moonves and Bruce Rosenblum -- for their support as he underwent rehab.
"I have a lot of work to do to be able to return the support I have received from so many people," Sheen's statement said. "Like Errol Flynn, who had to put down his sword on occasion, I just want to say, 'thank-you.'"
CBS executives have said that they were increasingly worried about the sitcom star but that there was little they could do because Sheen showed up to work on time and fulfilled his contract.
CBS Entertainment President Nina Tassler told TV critics in Los Angeles in January that there is "a high level of concern. How could we not? This man is a father. He's got children. He has a family. So obviously, there's concern on a personal level. But you can't look at it simplistically. Charlie is professional. He comes to work. He does his job extremely well. It's very complicated."
Addiction specialist Wandzilak said that just because Sheen shows up to work does not mean he is well.
"Sure he goes to work, but that's not the same thing as having quality of life," Wandzilak said. "And he also has a whole team of people around him that are getting him to work."
Getting celebrities sober can be very difficult because several people rely on that celebrity to support them financially, Wandzilak said.
"You're not just intervening on an individual, but a small industry," she said. "Charlie Sheen is a small industry and he has many people working for him and many people that need him to show up for work. ... Because they're invested in him showing up, the truth is they're going to be unable to put his health first."
On "The View," actress Whoopi Goldberg said she related to Sheen and that, for many years, she was a functioning addict.
"I went to work because I knew that if I didn't show up, a lot of people would be out of work, and I wouldn't get a check and would not have the lifestyle that I needed to buy my drugs," she said. "Until Charlie makes the decision that he's ready and willing to stop doing what he's doing because he can't do it anymore, he will do that. But he's not there yet."