George S. Ledyard wrote:
This is just another training opportunity... he was being a butt... you get pissed off. You are pissed, not really because he was a jerk, but because he showed you that you aren't yet as good as you'd like to be. If you were better, he wouldn't have been able to do that to you... This isn't a failing or a value judgement, it's just a statement.
He got you on two levels... first, he got you on the technical level. You couldn't move him. Depending on the level of experience you have and the relative size and strength mis-match he presented to you, that might have been completely expected.
But he also "got you" on the emotional level. You "contracted" around the emotional attack he gave you by trying to make you smaller. You got pissed off because you bought into it, you let him and now you are mad at him. You talk about people "taking advantage of your good nature". That's just a relection of your own perceived vulnerability. If you are confident and centered in yourself, his being a jerk simply means he doesn't "get it". It should have no effect on you since it has nothing to do with you.
These interactions, which we all have, are opportunities to see what we need to work on to be better.
I really hate quoting the entirety of a large post, but this is a great point.
It holds true regarless of Uke's intent. It's an opportunity for practice whether or not Uke's being a jerk, trying to teach you something, or stiffening from panic. Uke is actually irrelevant. For me, this sort of situation is one of the best things aikido forces me to work on. When something like this happens, it shows me that I'm off-balance or out of center, based on the fact that I get upset. If I was centered, I wouldn't be bothered. So as much as it makes me sound like a dirty hippy, I'm grateful when I get stuck like this, because it reminds me that it's not about the ego, and it forces me to acknowledge that I'm not beyond my ego, however enlightened I may have tricked myself into thinking I am ^_^