How to over come Depression and anxiety 

Let's understand psychology and metaphysical concept with the help of 
The Law of Attraction
it means: Whatever you think and feel strongly about, you attract into your life.
In simple words: Positive thoughts attract positive things, and negative thoughts attract negative things.

The Law of Attraction says that there is a force that is very powerful, whose strength knows no limits, It is infinite and if we connect with this force, it will solve all our problems.

As a muslim we know about the power. it's "ALLAH"
IN QURA'AN 
(Surah An-Najm, Ayah 39) “For every person is only that for which he strives.”
(Surah An-Najm, Ayah 40–41) "Indeed, his effort will be seen, and he will be given its reward"
There are other verses like this in the Quran.
so we have to follow this formula with "pukhta tawaqqul" . 
Good intention + effort + trust in Allah → positive outcomes.