Is Going On Retreat Selfish?

Recently I was asked by a dear friend, doesn't it seem selfish to go on retreat for long periods of time (not sure that was the exact wording, but it was along those lines). It really caught me off guard and made me really think about this.

My conclusion is that we all have a part of us that burns bright inside, an inner light shale we say. By going into retreat, it allows a person time to reflect on where this light comes from and helps us peal away and understand what obstructs this light. In my own personal experience it's my own selfishness and attachment that prevents my light from flowing like a wild river.
When I leave the retreat I feel that my light or love flows better, and I'm a better person to everyone around me and this echoes out as those around me. 

To me, understanding myself doesn't just help me, it helps everyone I come into contact with and that doesn't seem selfish to me, it feels the opposite.

It was a lovely question that really made me think about this topic deeply and has made me appreciate why I go on retreat more. So i'm thankful that I was asked this question.