Queen Esther was an orphan whose father passed away when Esther was in her mother's womb. Her mother passed away when giving birth to Esther. Her uncle, Mordekhai, who brought her up and married her (according to Rabbothenu, z"l), accepts the fact that she was taken away from him to marry Ahashwerosh. Our Rabbis of blessed memory say that Mordekhai knew through Divine inspiration that Esther was taken to the palace to serve a national purpose.
Perhaps we would expect an orphan, who had never met her parents to grow up with a chip on her shoulder, questioning "Why me"? Would her trust in people be shaken knowing that her uncle/husband thought it was necessary for her to be taken to Ahashwerosh's palace?
Esther spent five years in the palace before she finally realized what her mission was. It seems that pain and suffering may have been part of Esther's life. In spite of, or perhaps because of that, she was the perfect person to rise and save her Jewish people.
Challenges and tests are part of every person's life. It is our choice whether we use them as a springboard for growth and greatness, like Esther did, or allow our difficulties to pull us down, paralyzing and inhibiting us from fulfilling our unique goal in this world.