You're dealing with people so could be anything realistically ...depression , relationship issues , drug addiction etc etc ...I got a completely different feel - I thought that they were personal issues that some players were dealing with. These types of incidents come to the head coach, but not to the assistants.
These young guys have lives outside of the footy bubble - and whether it is a sick relative, a problem in your relationship, some financial problems - they all influence individuals differently.
I reckon his point was that he rarely got involved in those types of things, but now as head coach - it's part of his job, and a responsibility that he takes seriously.