Suffering is a sign that you have accomplished great things in Christ, be those mental, psychic, or physical. For Christ suffered; that is clear from the liturgy of Holy Week. He suffered lonelines from the Father, betrayal of his apostles, and the greatest suffering known to humankind from the Cross.
What should we do when we face suffering? If we realize that we become like Christ when we suffer, we can take consolation. After all, what we seek to do is to be like Christ.