To trust in Divine Providence basically means not pretending that one is God. One gives ones' entire life over to God and lets Him direct this life. This abandonment to Divine Providence does not guarantee a life of ease, although one may have great peace in the midst of troubles.
Many things must be attributed to Divine Providence, such as serious illnesses, like cancer, or loss of job, status, even home.
To stand back from the evil of the moment and say, "Jesus, I trust in Thee" is the ultimate act of love. If we trust God, we know we are loving God. Those who play God, neither love or trust Him.
The lives of the saints reveals little ease and comfort. In fact, an examination of the lives of the saints points us always in the direction of deep suffering.
One may ask why allows suffering. The answers vary. But, the main reason suffering is allowed has to do with the fact that God see individuals' free wills as sacred.
He also used suffering for our purification, and for intercessory prayer. It can also be for reparation of one's own sins and the sins of others.
However, in my opinion, the main reason for suffering is that one is invited to share in the Passion of Christ.
When one loves Christ, one wants to be with Him always, even at the foot of, or bearing the Cross.
Trusting simply means using the gift of faith given in baptism.
Hard? Yes, Impossible? No.
BBS.