Every one in my family, mother,brother,sisters had emotional problems. My father did not. He never beame a jw. I thought I had lucked out and then at the time I wanted out I came down with severe depression. My ex and my children had problems. All of them that left jw's have improved and got over the depression etc.
I have no reliable statistics but my observations of others in the org. leads me to believe that mental problems of one or another kind are rampant in jw's
Balistic your mention of the person who died in auto crash brings this to mind.
For a time I was a sheriffs deputy. At that time at least, all auto crashes involving only one auto and especially if only one occupant was investigated as a possible suicide.
Those that involved a vehicle suddenly crossing the line into oncoming traffic to colide with a truck were always considered a possible suicide. It was believed that many of the crashes were intentional but not proved.
So your suspicions may be correct.