Michael Cera has dumped his long time girlfriend Charlyne Yi because, well he is an actor and wants to have sex like Russell Brand. According to Star, Michael got tired of only dating his girlfriend of three years and wanted to play the field. "He's been with her since before he was superfamous, and now all these girls fawn over him. He's itching to date other people."
Well if he dates too many people he will probably start itching, and it won't be pleasant. He also needs to realize that he plays one character and one character only and so his fame is going to be very fleeting. There are only so many possibilities for someone of his range. What he really needs to be doing instead of screwing over someone who is loyal to him and gave him a charity date when he wasn't famous is be loyal to the people over at Arrested Development who also were with him before he became famous.
Loyalty just goes out the window in this town when you get famous. It sucks but there isn't anything I am going to be able to do about it except call people out when they do something. Charlyne is said to be crushed. What makes this even more painful is they are doing a press tour for Paper Heart which is a movie they did together.