Power steeering problems

I have a 1998 eagle talon. I let a friend borrow my car and now I'm having problems with power steering. When car is at idle , it's real hard to turn steering wheel, when I step on the throttle, it turns a little easier. As soon as I let off the throttle, hard steering again. I checked the fluid. Could it be the power steering pump?
Thanks in advance.

the clutch on the pump is slipping, as long as there's enough fluid in the reservoir, then the only solution to the problem is a new pump

thanks buddy