From "Life Goals Matter to Happiness: A Revision of Set-Point Theory," published in 2006 by Bruce Headey, of the German Institute of Economic Research. Emphasis is mine; note that SWB is an acronym for subjective well-being.
SWB theory, as currently understood, has the depressing implication that one's level of happiness is extremely hard to change because it depends on characteristics one was born with or which are developed early in life. The most widely endorsed theory at the present time appears to be set-point theory...All these theories claim that a person's set-point or baseline or equilibrium level of SWB are near-automatic consequences of hereditary characteristics and personality traits. Conscious life goals play no role in these theories and major life events are viewed as having only a transitory effect.
In recent years there has been some questioning of set-point theory and its relatives. Some life events are so severe that victims never recover back to their previous set-point or equilibrium level. One such event is the unexpected death of a child...Repeated spells of unemployment, although not a single spell, have been shown to have a 'scarring effect' from which most people do not recover...Getting married temporarily raises the SWB of most people, but then most revert to their previous set-point. Entertainingly, the only positive life event which has been unambiguously shown to raise the SWB set-point is cosmetic surgery.
I should note that the takeaway from Headey's paper is that people who pursue non-zero sum goals generally have higher levels of subjective well-being. Basically, you're better off orienting your life towards family, health and altruism than towards financial success and social status. Heady also investigates internal locus of control as a factor in SWB:
People who have an internal locus of control believe that they can to a considerable degree control their own lives, that success or failure are in their own hands...There are theory-based reasons for believing that success in the pursuit of life goals may be related to internal locus. People with high internal locus tend to be persistent in pursuit of coals and have relatively good coping skills. By contrast, people who rate high on external locus of control tend to believe that outcomes are due to luck or the influence of powerful others.
What makes for a happy person? Part of the answer seems to be a personality characterized by a high level of extraversion and a low level of neuroticism, coupled with a desire to pursue non-zero sum family related and altruistic goals...Such a person is likely to be happier in the first place, and to have a reasonable prospect of becoming happier over time. The role of internal locus s interesting in this context. Internal locus is probably best not thought of as a more or less fixed personality trait like extraversion or neuroticism. It is a disposition to take responsibility for one's own achievements and failures, and this is associated with persistence/perseverance and good coping skills. It is tempting to suggest that internal locus may be the link - the link in terms of perseverance and skills - between having non-zero sum goals, pursuing them effectively and increased life satisfaction.
So: Work on your priorities, and put family, friends, and health first. Take responsibility for your failures and accomplishments.
And in the meantime, get the facelift.