Rabbi Lazer Brody has publicly stated that
the root cause of most mental health issues
is the lack of emunah and bitachon.
If you truly trust in HaShem at all times,
and always believe “Gam Zu LeTovah”,
then much of your anxiety and unhappiness
should vanish.
Another root cause of most mental health issues
is spending too much time remembering the past
and spending too much time thinking about the future.