R.D.
I had a job like that once. My supervisor was awesome; the girl training me was NOT. She was totally intimidated by me and went out of her way to do a half @ss job training me, so I looked like the idiot. She complained about me constantly... and then would take no blame for not teaching me what I was supposed to be doing!! I finally went straight to my manager, apologized that something wasn't clicking, and that I would appreciate any effort on his part to help close this communication gap. Not only did it take only 4 hours to reach a very full, complete understanding of my job duties, the girl who was training me was terminated, I took on HER responsibilities, and got a raise almost double what I was making.
I'm telling this because THIS is why you should just talk to him :)
Best wishes!!