We are not all called to become the next Mother Teresa, working with the poorest of the poor in society.
At the same time, some of us are called to such a life.
What we need to do is to actively discern God's specific calling for us in life that takes us beyond ourselves and into mission.
Mission in life
St. Francis de Sales explains this process in his Introduction to the Devout Life, encouraging his readers to, "select some special virtue at which to aim, not as neglecting any others, but as an object and pursuit to the mind."
He then goes on to illustrate how each saint had their own personal mission:
Saint Louis counted it a privilege to visit the hospitals, where he used to tend the sick with his own royal hands. Saint Francis loved poverty above all things, and called her his lady-love. Saint Dominic gave himself up to preaching, whence his Order takes its name. 53 Saint Gregory the Great specially delighted to receive pilgrims after the manner of faithful Abraham, and like him entertained the King of Glory under a pilgrim’s garb. Tobit devoted himself to the charitable work of burying the dead. Saint Elizabeth, albeit a mighty princess, loved above all things to humble herself. When Saint Catherine of Genoa became a widow, she gave herself up to work in an hospital.
God does not call everyone to the same mission. Instead, he wants everyone to add something unique to the great tapestry of the world.
St. Paul talks frequently about this idea in his letters, such as in his letter to the Corinthians:
Some people God has designated in the church to be, first, apostles; second, prophets; third, teachers; then, mighty deeds; then, gifts of healing, assistance, administration, and varieties of tongues. Are all apostles? Are all prophets? Are all teachers? Do all work mighty deeds? Do all have gifts of healing? Do all speak in tongues? Do all interpret?
God wants all of us to contribute something to the greater good of society. It is up to us to listen to his voice and let him guide us to know where we should lend our gifts and talents.