We humans have our good and bad days and some of us experience periods of hardship and/or unhappiness during the course of our lives. Aside from clinical depression, which warrants professional intervention, the causes of unhappiness are generally problems that we, ourselves, can control and agreeing that we deserve to be happy is the first step.
Other measures, not to be taken lightly, may include ending a relationship, finding a new job and learning to distance ourselves from past influences that set us on the course to unhappiness. The opinions, beliefs and advice of others can have long term consequences and self respect is often the victim.
Wanting to be happy is not self-indulgence. Neither does the effort distract us from being kind, charitable and empathetic individuals. Indeed, happiness may be contagious and our personal sense of well being will likely benefit others as well.