This is certainly possible. I should expand my definition as not only sustaining life, but rather avoiding two extremes: one scenario in which all matter repels

This is certainly possible. I should expand my definition as not only sustaining life, but rather avoiding two extremes: one scenario in which all matter repels from all other matter (on an infinite scale) and another in which all matter collapses on itself. These events would seem rather cataclysmic for our universe as a whole, but that could be chalked up to our limited understanding.