Have faith.
And Jesus said unto them, Because of your unbelieve: for verily I say unto you, If ye have faith as a grain of mustard seed, ye shall say unto this mountain, Remove hence to yonder place, and it shall remove, and nothing shall be impossible unto you. Matt. 17:20.(KJV).
Why did Jesus use the mustard seed as an example?
From a tiny mustard seed, a massive tree grows.
From small beginnings, great things develop.
Jesus did not say you must be able to remove physical mountains.
He was talking about your daily problems.
Jesus did not say your problems will disappear immediately.

When you have problems and have faith, you will not allow those problems to make your life a misery.

You will have the faith to remain trusting in the ability of God.
You will know everything will turn out well.
God is at work in your life.
Daily read the Word
Daily Praise Him.
You will not be depressed.
Do you complain to your friends about your difficult life?
What do you tell them when they complain about their own life too?
Do you have enough faith always to be joyful?
Can you encourage your friends when they are depressed?
Application to the Christian life:
Trust God.
Develop your faith into a tree.
Remain strong.