Without seeing the entire chart, it's hard to say. Squares are always about internal conflict. If there is also an opposition involved, it could play out THRU the other person or a relationship with another person.
The Moon represents habits, patterns in one's life, cycles, health, one's mother, one's upbringing and the habits of the family during that upbringing, and, of course, the "emotional mechanism" - meaning how you feel, why you feel certain things, the way you deal with your feelings.
So....big subject.
LIN