The Savior taught His disciples, 'For whosoever will save his life shall lose it: but whosoever will lose his life for my sake, the same shall save it' (Luke 9:24)."I believe the Savior is telling us that unless we lose ourselves in service to others, there is little purpose to our own lives. Those who live only for themselves eventually shrivel up and figuratively lose their lives, while those who lose themselves in service to others grow and flourish—and in effect save their lives.
There is nothing wrong with violence in itself. In any particular case, whether violence is good or bad depends on how it is used and the purpose for which it is used.
It is worthwhile for one to make an effort to achieve happiness. Just as the purpose of a plant is to grow, so it is that the main purpose of every human being is to survive and to grow until death.