Who you're being, at any given moment, is reflected in your environment. It's not that your environment magically changes, it's that your filter changes. You notice only the things that reflect who you're being at that given moment.
We all know people who only focus on the negative, give them any situation and they will still find a way to complain about something. It's annoying and frustrating for everyone else but they're not consciously doing it; they're on Autopilot.
It's not that everything around them is bad, it's that who they're being doesn't allow them to see the good things.
Who they're being is reflected around them, not the other way around. We react to things around us but those things reflect us. Again, it's not that your environment magically changes, it's that your filter changes.