I hope this isn’t a D.F.Q. but, is there an “average” distance between the stars in the visible (known) universe?
I recall reading that the average distance between stars in a galaxy is approximately 5 light years. But galaxies are very far from one another.
What about a globular cluster?
This link supports pinkfreud’s 5 light years and it isn’t the only one, but I’ve found other websites that say the average distance is 3.26 light years, aka a parsec, and yet another website that says 4,300 miles when 1,000 = one light year. And a page that had diagrams drawn out in crayon. Anyway. 
These two pages both say the average distance between stars in a globular cluster is approximately one light year. The former gives “just over 3 light years” as the average distance in “solar neighborhoods”.
Stellar density increases as you approach a spiral galaxy’s central bulge. Density also increases towards the center of elliptical galaxies. The density of a globular cluster can approach one million solar masses per cubic parsec in the central regions.
The actual stellar density in the region of the sun is a little uncertain, as no one yet has a handle on the proportion of dim, and difficult to see, red dwarves in the milky way.