Seperation Date

My Spouse left a house in Aug of 08 as well as he is revelation me which this is a date of seperation even though he didn't file for divorce until May of 09.  He didn't do this deliberately which we can tell, but it is an area of row right away as well as do we have any real drift for fighting this in court.  My arrogance is which you went to 2 or 3 matrimony couseling session in a tumble of 09 so we would reason which a clock upon a 2 year period in PA would start in Dec of 08 as well as not Aug of 08