If I understand you right, you're asking why do the galaxies not behave similar to what we are told the universe does. The universe isn't like a mass of galaxies, like a galaxy is a mass of stars. It's a different model to the star system, galaxies etc we know to exist within the universe.
Inflation ended, but expansion didn't end. Inflation is just a very specific and short period after the big bang that is defined by certain phenomena. After that the universe continued to expand but behaved a bit differently to what it did initially.
Dunno, there is solar wind, but it's a st