I really enjoy self-help books. Sure, they're often hokey, and often little more than reminders about the obvious. I still like them. They remind me that I have some ability to change my life for the better, and all I have to do is to work at it.
It could be argued that one cannot affect long-term psychological change--that one is likely to remain about as happy and healthy as one has always been. I don't believe it.
And even if it were true, would I lose anything by expending my efforts on things that might help me live a better life? Well, that depends on what I give up, but if what I give up is merely a string of entertainments? Or if what I give up is a long career in a job I don't care about, so that I can afford a long string of entertainments at some later date? Don't get me wrong; I'm not opposed to entertainment.
There's plenty of reason to believe that we can change our lives for the better--not the least because believing the opposite--that we can't change our lives for the better--is both a self-fulfilling belief and a sad state of affairs if we can see ways in which we'd like our lives to improve. Given the reciprocal causal relationships between our emotional states and events in the world around us, change in our physical and/or social states in the world can also reflect or lead to change in our psychological states.
Without doubt we are capable of changing our situation by, for example, finishing a dissertation or other project. This change can certainly connect to change (at least temporary) in our psychological states.
Can we, through practice, bring ourselves into more positive mental states that facilitate our ability to finish projects and accomplish other change in the circumstances of our lives? I believe so. I believe that that emphasis must be placed on practice--which, indeed, is not a surprising contention, given that spiritual traditions usually both claim their ability to improve mental states, and the importance of practices in bringing about that change.
Self-help books, I think, get a bad rap for the same reason that people want diet pills: easy answers are being sought. I've never read a self-help book that said that the promised improvement would be effortless. Most self-help books I've read stress the importance of making consistent, long-term alterations of our behavior--in other words, practice.
Having accepted the fundamental role of practice, I can read self-help books not with the expectation that they will deliver some easy panacea, but in the hope that they will suggest to me possibilities for developing my own practice.
Given that practice is also the means to completing a dissertation--by writing every day--and the means to completing most projects in life, developing a self-help practice seems to me a project that can withstand the most skeptical arguments that I can muster. And I am, in many ways, a philosophical/epistemological skeptic.