Do Cittanupassana(noting of mental activities). When a mind of anger arises, simply note it until it goes away. When a mind of sadness arises, simply note it until it goes away.
The depression comes because you are clinging to the body as 'yours', 'yourself' etc. What you take as your body is going to be nothing more than ashes or soil & bones in less than 100 years.
You were born as a human due to a past good Karma, but you got mutilated possibly due to a past bad Karma. Perhaps the results of that past bad Karma will be exhausted after this life.