Happiness seems to come without effort when a person values themselves in a healthy way that is independent of accomplishments, controlling others, being controlled by others, material possessions, their background, the situation at hand, etc. Unhappiness (depression, addiction, and other such things) all seem to share a variable that is the opposite of that where an unhealthy individual has desires and expectations on external things in order to be happy - including at times controlling others, or being controlled by others, or shopping, or self-destructive behaviors, or escaping behaviors, etc. Satisfying the short-term desire (the insatiable "I want"), can provide a temporary respite, but as long as the root cause has not been addressed the individual really isn't going to get better. Along with genetic predisposition, environmental issues, family background, personality/temperament, we have many of the key ingredients that cause the disease of addiction. And once it starts, an individuals brain chemistry and body chemistry begins to change in ways that perpetuate the addiction. And those with a genetic predisposition are likely in a place where the perpetuating process is already active.
I believe that this is why addiction therapy focuses on helping people understand their value as a person independent of their past, accomplishments, and material possession. And for folks suffering from addiction it also includes interacting with other addicts going through the same process, because it's really difficult (or maybe even impossible) for a non-addict to understand what it's like to suffer from the disease of addiction. And it's not a matter of "self-control" or "willpower". A non-addict has no idea the amount of "willpower" an addict has.
Using the religious metaphors, it sure seems that is the essence of "cleansing of one's sins", "redeeming one's self", being "reborn", et. al. on a very personal and life-saving level.