Jennifer Esposito (left) and Christina Applegate
INF; Juan Rico/Fame
As Christina Applegate
's outspoken best friend on the ABC sitcom Samantha Who?
, Jennifer Esposito says of her costar's brave battle
with breast cancer, "We can take a lesson from her."
"She's a huge inspiration," Esposito, 35, told PEOPLE at Monday's 8th annual 24 Hour Plays on Broadway, where writers, directors and actors like herself pulled off six original short plays all in 24 hours.
"She never stopped once to say, feel sorry for me. She doesn't look down and doesn't look to the side. She just looks forward and keeps going," said Esposito of Applegate.
"She's a very strong lady, one of the strongest ladies I know."
Having not slept in 26 hours – owing to shooting her TV show, packing to move into a new home, then catching the red-eye from L.A. and performing in the New York City dramatic festival – Esposito is stimulated by Applegate's courage and work ethic.
"Look, I get tired, and she's got more work and other issues to deal with than I do," says Esposito. "She works so hard. She's a tough fighter and she just keeps going."
What helps Applegate – who is now cancer free
, after having undergone a double mastectomy – have a positive outlook?
"It's just her. That's who Christina is," said Esposito. "She did what she had to do and that takes a lot of strength. I'm so impressed with how she handled that and how she continues to handle herself."
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