female orgasm

My wife and I are crazy sexual active. Especially since I'm gone half the time for military business. Be when I get back, it's on.
I have a question that's been bugging me forever. Do all women physically cum or not?
She says not all women do, and when I get her off, which is multiple times, her body goes crazy, back arched, legs quivering, moaning like hell but no physical ejaculate.
Is she faking it?