“Let not your hearts be troubled. Believe in God; believe also in me.”
Let your heart be ruled by what God has promised you and what scripture tells you and not by what you see.
God does not want us dwelling in anger or any other negative, destructive feelings we may have at the moment.
This is why we should be honest with God and when we pray to God, we should come as we are and not pretending to be someone we are not.
If we are honest with Him, we will feel a sense of relief and that should lead us to a deeper relationship with God. A deeper relationship will definitely lead to less discouragement.