Q: How to develop the mind for good things?
 A: The mind is not developed for good things as such , the mind develops in the good .  Since it is not to look for the path to good things , rather , good is the only path . And this is real development .

Q: Do I have to deprive myself of everything in order to reach God ?
A: God is total fulfillment , there is no deprivation in Him . The path is surrender , true surrender . Since total fullness is in God , where is then , the deprivation ?

Q: How to forgive the ones who have hurt me ?
There is no how . To forgive is to understand that to hurt is spiritual ignorance , lack of knowledge of the Science of God . The person who tries to hurt others is only hurting himself/herself . The minimal compassion implies praying for them .