Some feelings are residual: not based on a current reality, but rather a perception and interpretation of reality in response to past experiences.
Values fluctuate. Just as your values have changed over time, so do the values of others. Accordingly, not everyone will value the same things as you, just as you no longer value certain things you used to value.
Your current perception of reality is not a necessary truth about the world. Other people might interpret the world in a different way, or even you might see the world differently in about 5 minutes.
There is no novelty without the mundane. Often, we want our lives to be mostly positive, but we have no notion of positive without a notion of negative. The exciting can only exist in opposition to the boring. Life encompasses all extremes: joy in relation to grief, and so on.