It is frustrating to be in this situation! As annoying as it can be, I always have to ask myself what I am doing wrong, or how can I move my body so as not to get stuck like that. It is usually something like having an angle not quite right, or being off-center (for me).
Sometimes uke doesn't know how to move properly either, or doesn't understand that by stopping the technique (at 5th kyu) that he/she is not opening themself up to learning which is done both through being nage as well as uke.
I don't have any really good suggestions on how to respond, but my first reaction would be to not train with that person for a couple of days until I had cooled down and assessed the situation (was it something I was doing? etc.) and then try to practice again with an open mind. Easier said than done sometimes. Maybe you could just talk with him and ask him what was going on?
Hope this helps even a smidge....