Aside from our local star, Sol, stars can form close together, they can even form binary (or larger) systems. It just so happens it didn't here. Which might just be part of why we came to be here rather than somewhere more complex.
Fact is that he stars have to be somewhere and if too many were near us life may not have had the conditions it needed to evolve something like humans.
Yes the universe has ben expanding ever since, although at a more sedate pace since the initial inflationary burst.
Unsure I follow your question. A galaxy tend to stay roughly together not splitting apart due to the expansion of space because of the gravitational attraction of the stars etc..
The thing is things form where they find themselves and we only have one local star which we orbit.
Hope that helps.