Can't remember name pls help

It's about a small actor getting a gig with this famous guy. He gets really into the role to the point where it's hard to distinguish real life from fantasy.
I remember he gets his heart broken because the other actor had a wife in one scene which he didn't know about and he broke down crying after he finishes the scene. He began agonizing about the actor having a wife in real life and idr the rest.

Sorry for the vague description lol
Please and thank you
(人 •ᴗ•)
(◍•ᴗ•◍)✧*。