One thing I've learned through the television program CSI, is that the evidence doesn't tell all. In the case of user experience design, neither does user feedback.
If I just blindly follow the user feedback, without combining principled thought into your designs, I would just end up with very little functionality or something unusable. The fact of the matter is, any time I come into such feedback, either positive or negative, there's always something to be learned here. Most of all, question the fundamentals - question the feedback.
I ask myself why someone says what they said. Is there a better way where I'd be able to change that perspective but tweaking my design? I usually answer - "Of course". And that's where better ideas come to solve the problem. I focus on the desired result, asking myself - "I want them to say -this- about the interface, now how could I go about getting that result?"
I look at many things in user feedback.
1. Patterns - namely, user habits.
2. "Negative" feedback - it's not always negative. There's actually more to learn from it.
3. Why it was interpreted the way it was - find the causes.
I then look at possible steps to correct or enhance the user experience in small bits at first, then use a bit of my subconscious (i.e. experience) to guide me. In these steps, I usually do several quick prototype iterations either in my head or on a whiteboard where I can explore solutions and its interactions to solve the inherent usability problems. Then I translate the best solutions into the actual mockup.
This is just one of the ways where digesting user feedback is taken in little steps - and systematically at that.