J. S. Mill wrote, "Those only are happy ... [who] have their minds fixed on some object other than their own happiness. " He explained that people should pursue a life goal and experience happiness en passant. Mark H. White made a similar point. I think this view is valid and timely.
To gain happiness, a person needs to increase self-awareness of values and life goals. One man might become aware, for example, that he really doesn't like the "rat race" and prefers a leisurely life. Another might become aware that he loves to work. The former will find happiness in a job that is minimally challenging or even working parttime, whereas the latter in a job that is very challenging and requires a lot of work, maybe more than full time.
If one is focused on partying, odds are you are not focused on fulfilling your life goals. In that case, you may be unhappy. As a young man, Malcolm X, for example, partied day after day while becoming increasingly unhappy with his meaningless life. So he found Islam and changed his life. He didn't find Islam to be happy; he found it because it expressed his values. Happiness came in passing because his life was now meaningful to him.
Mark White has validly brought the rich philosophy on happiness to the psychological topic. Too much of psychology is focused on simple ideas about happiness as the excess of positive over negative feelings. Too much is about dualism: pleasure/pain; intrinsic/extrinsic; behavioral excitation/inhibition. Not enough attention is paid to meaning, fulfillment, values, needs and life motives. I think White's summary of the situation is accurate. He also noted, correctly, that some psychologists have sought to avoid this issue.
Obviously, people who are anxious, in pain, or having some significant psychological problem will report less happiness than does the average person. This is partially because virtually all people with serious psychological issues have low self-esteem, which in some clinical circles, is almost synonymous with sadness.
Focusing on one's own happiness absorbs you in yourself. If you are a gregarious person, you will be unhappy focused on yourself because it may defeat your social goals.
The concept of happiness was discussed in ancient Greek philosophy. I congratulate Mark White for seeking to connect happiness research in psychology with happiness scholarship in philosophy. I have read a lot in psychology, and I read the philosophical literature on happiness, and I think it is valuable to link up the two literatures. Psychology would benefit.