abcdefg - Without knowing exactly what is bothering your student, I can't tell you precisely what I'd do. But in general, I try hard to get to the source, and am not afraid to be blunt about it. If a student complains, I make them be specific, but I don't necessarily take them at their word. I have one student who will say "that's stupid" about just about everything, and another student who will say, "that's too hard."
In both cases, I think they are saying, "I am not feeling good about myself right now." I tell them that if they are feeling overwhelmed, that I am willing to go slower, or to even go backwards and review some things to get their confidence up. I also try to find something positive to say. The first girl ("this is stupid") has taken off once I backed her up - new books, rather than literally backing up - but quicker mastery for her.
The second girl ("too hard") thrives on attention - including negative attention, so the best response I have for her is ignoring her comments. Or calling her bluff. "Okay, if you don't feel ready, we can do the old lesson for another week." The worst thing I can say to her is "No, it's not." Then it becomes all too easy for her to prove she is right. I might say, "If it feels too hard to you, then we don't have to do the whole thing - maybe just the first part to start, until it feels easier." Once it becomes a challenge to her, she jumps right in.
My concern with your student is that it might be attention-seeking behavior, and too much focus on it might prolong the problem. I feel like you need to be blunt with him. Tell him that you see a problem, and you need his help to fix it. Then spell out exactly what you are seeing, and ask him what he thinks the two of you can do to make it better. If he owns the solution, he might be more inclined to make it work.
One of the things I love about teaching is working with the individual - no one-size-fits-all. The second girl continues to be a challenge - her whining drives me crazy sometimes. But we have come a long way, and I actually enjoy teaching her now and am pleased with her progress.
I also wanted to mention a 10-year old 4th grader I teach. She is little miss sunshine, so she certainly doesn't match your student that way. But we were in need of some supplementary material for her, and she is in level 2 PA. She wanted jazz, and I was having a hard time finding an appropriate (easy enough) jazz book. But I gave her Martha Mier's "Center Stage" book 2. It is a bit above her level, so we've had to take it a bite at a time, but she loves it. It is great music - a lot of fun to play, and very motivating.