Am I overreacting? Or should I just be grateful to have a job?

I am an oil and gas project analyst for a government contractor located in Fairfax, VA. Sometimes, I feel really lucky just to have a job in this economy. BUt there are other times when I feel that maybe I've stayed too long, and I am just putting up with a bunch of BS that is completely unnecessary. For instance, I've asked my hiring manager to give me work of substantial responsibility and content so that I can learn on the job -- to no avail. Other project managers are trying to help me out, but they've already hired their own research assistants and analysts. I'm just this one extra person to whom they go for work that don't really carry much importance (e.g. writing proposals, pulling data into Excel). So a few days back, when my hiring manager asked me to send him my resume and an introductory paragraph of myself, he came back to me with a harsh e-mail saying, "You need to re-do your resume and introductory paragraph. Your clients are not going to be impressed with your work on proposals and pulling data into Excel.") I don't know what to say to him. What I want to say is, "Well, that's all I do here. And when I ask you to give me responsibilities, you just ignore me." But I can't really say that. Is it time to just move on from my job, and forget about my original goals when I came here, which was to gain meaningful job expereince and earn a work-related bachelors degrees in computer science and accounting???? Or is this just one particular instance at work that has set me off, and I just need to move on????