Put the camera away for a while, and don't look at your own work. In fact, don't even look at anyone else's work. Just forget about photography for a while and move on to other things. When you start to miss it, I mean really miss it to the point where you don't feel the frustration of that brick wall anymore, then start looking at other people's work and be inspired by it. Then it's time to get the camera out again.
I did this, and I feel much better about what I'm doing now. I enjoy it, I feel rejuvenated by it, it brings peace to my soul. When it starts to frustrate me again, and I'm sure it will at some point, I'll stop again. Don't misunderstand me, I'm not saying one should not be challenged by things, but there is a difference between being challenged by something and feeling frustrated by it. Life is short, it is important to recognize the difference.