This will blow your mind. This blew my mind out of the water. Many times, a curse comes to me in the disguise of blessing. Thus, evil exits to provide with Free choice. Instead of getting angry with G-d I am learning see the blessing that is hidden from me.
“Moses urged the Jewish people to realize that G‑d gives them the choice between good and evil. Their choice will result either in a life of blessings or one of curses.
[Moses told the Jewish people in G‑d’s Name,] “See, I set before you today a blessing and a curse.” Deuteronomy 11:26
A Divine curse is actually a blessing that is too great to be revealed within our limited world and must therefore be “disguised” as a curse. Our challenge is to see it in this perspective, rather than falling into the trap of becoming angry with G‑d. Thus, pain and negativity exist in order to provide us with free choice. Free choice, in turn, exists in order to enable us to earn the rewards for our choices, so we need not feel unworthy of the blessings that G‑d bestows upon us.
When we recognize that evil exists solely to provide us with the free choice to reject it, our struggle with it becomes much easier.1 Likutei Sichot, vol. 4, pp. 1339–1342.