Why is Cammy fired in Typical American by Gish Jen?

Cammy works as a secretary in the Foreign Student Affairs Office. She's the one who gives Chang his new American name of Ralph. She takes a liking to Ralph, which is more than you can say for her attitude towards her job, which she heartily detests.
Cammy's relieved of her duties because it seems—although it's never conclusively established—that she's been having an affair with the dean. Mr. Fitt, Cammy's boss, is none too happy about this. She's also been slacking on the job by having one too many long lunches with the dean, and this gives Mr. Fitt a convenient excuse for letting her go.
As for Ralph, he feels rather disappointed that Cammy's been seeing another man. He thinks that if he'd been able to buy Cammy a car, then she would've fallen in love with him. But as his friends rightly point out, if you have to give someone a car, then they don't really love you.