Christ doesn't want us to be controlled by our emotions, but He does give us freedom to feel them when it's appropriate. It's our responsibility to know how and when to express them appropriately.
Sometimes even when we're walking with the Lord and have cast out demons, we can still struggle with strong negative emotions. But by using certain tools, we can still find freedom.
Once we decide to follow Christ, and live according to the pattern he set for us, Satan and his forces will do all they can to stop us. They will twist our emotions so that we're ineffective in the assignments God has for us. But just as Jesus overcame Satan by rising from the dead, so can we.
Victory from our negative emotions cannot be found apart from a right relationship with Christ. Once we decide to be a disciple of Jesus, He will love us by disciplining us. Sometimes with negative emotions. Through prayer and repentance, we have hope and victory.