Are you being buried on stage or FOH?
If the keys are killing the bass in the PA, then the soundman is at fault. Any skilled sound guy would be able to EQ the two parts for seperation. Unfortunately "real" soundmen are like unicorns, you hear about em, but you you rarely find one!
On stage or FOH the key the solution is to boost/cut different frequencies on the two instruments so the occupy different sonic space. Difficult to do on a bass amp because usually the frequencies are set. If your amp has any flexibility in mid-frequency, find the frequency that makes your bass stand out the most and boost it.
Talk to your soundman (if you have one), and like the other said, talk to your keyboardist.