I stopped faking it in my early twenties. why I did fake it:
didnt know how to get there during intercourse
wanted him to stop waiting on me to do it
wanted to signal an end/move on
didnt want to actually do it, might pee
couldnt relax enough to actually do it
I dont need to fake it anymore for any of those reasons. if hes waiting on me ill tell him not to especially if I can tell its hard for him (giggity). guys wont care if you "pee" on them. and if I dont get it the first round he'll usually make sure I do the second. sometimes I have to force it but I prefer not to. now if I dont I just tell him so if hes not sure/asks.