"Not a single person on earth is always good and never sins." (Ecclesiastes 7:20)
Therein lies the need for God's grace. Grace is nothing that we can earn, but instead, is given freely to those who repent and believe.
Being a Christian isn't about having an easy life, a sinless life, or a life full of prideful accomplishments, but rather a life of recognizing we "still" sin (but are forgiven), that we can call on Him in times of hardship (as He'll never leave us), and a life of spreading the good news of the hope and salvation found only in Jesus Christ (as we are commanded).
Now go, and make disciples of all nations, remembering always, "To act justly and to love mercy and to walk humbly with your God." (Micah 6:8)