I have a 99 Dodge Durango and the driver side window will only go up if I help it up, do you think it is the switch or the motor

Most likely the motor.

A couple of possibilities here, try giving the tracks around the window a squirt of WD40, just in case there is mud or grime caked in the tracks. At the same time shoot a little WD40 down inside the window opening in the door to lube some of the gears and clock wheel. The other possibility is that a rivet or screw is jamming the mechanism. Roll the window up and down, listen for any grinding or hitting coming from inside the door, (Turn the radio off first). Listen to see if the motor labors in a certain spot and check inside the door using a small flash lite to see what is contacting the window oe mechanism. If you find that there is a binding and the motor slows down and this has been going on for some time, you'll need to replace the motor. Too much to do for home mechanic, take to dealer for servicing.