Abraham is a great example of someone who trusted and believed God was faithful to fulfill his promises even when things got difficult.
There are many things that aim to undermine our faith: our guilt, different diagnoses, depression, anxiety, fear, and various circumstances. God wants to build our faith and confidence to be so strong it can handle anything thrown our way.
What were your expectations for your life up to this point? What expectations were met? What fell short? What were exceeded?
The degree to which we are willing to let our emotions control us will determine our capacity to trust God. Simply put, trusting our emotions over God and his Word will lead us into a state of unbelief.