“I told you so,” is one of the most hurtful and harmful expressions one can say to someone who is a victim of betrayal, mistrust, heart break or loss.
Maybe we were correct in our anticipation and judgement of their situation but at the time of distress no one likes to be reminded of their negativities and weaknesses.
It is human tendency to feel guilty whether openly or secretly. Overwhelmed with emotions this person, who is already holding himself responsible for the consequences would not want to be reminded or reprimanded for the loss.
A conversation beginning on a negative note will never lead to anything positive. Therefore, if we truly care for the depressed person then we need to be compassionate towards him at the time when he needs it. At this time what he really needs is a listener not a lecturer.