...it is given unto you to judge, that ye may know good from evil; and the way to judge is as plain, that ye may know with a perfect knowledge, as the daylight is from the dark night. (Moroni 7:15)
So much of the insecurity felt in life is due to how decisions are made. It is possible to make decisions in such a way as to free you from doubt.
You can know what is right and what is wrong with absolute surety. The key is to understand how you should decide and when to reconsider what you’ve already decided.