The studies conducted by psychologists can be very helpful. Observations are helpful.
The problem lies in the treatment.
We can see the same parallel in conventional medicine.
For example, if you're feeling exhausted, it's very helpful to measure your vitamin levels. Are you low in iron, vitamin B-12, or something else? If your throat is sore, it's good to know whether it's the strep bacteria or a virus. X-rays and other diagnostic tools that require lab work prove immensely helpful in diagnosis (barring human error or faulty equipment, of course).
However, if you get strep 3 times in a month despite taking antibiotics exactly according to directions, conventional medicine doesn't have a solution except to give you increasingly stronger antibiotics...which also harm you by killing the good bacteria with the bad, making you more likely to get sick again.
(This is when you start imbibing probiotics, freshly squeezed citrus juice, and the right herbs to prevent a recurrence--yes, speaking from personal experience. At the time, I didn't realize I should also speak to Hashem about what message He was giving me with all the strep, but I should have done that too.)
Sometimes, conventional treatment is the way to go; surgery can save lives and prevent the need for long-term treatment.
So observation and then the diagnosis that comes from observation can be helpful.
This means that, say, studying 500 people for 20 years regarding mental illness, ADD, trauma, dysfunctional childhoods, etc., can be very constructive in understanding what is going on with people.
For example, a good friend lent me John Bowlby's A Secure Base. Inspired by his own upbringing by detached parents, his traumatic separation from his beloved nursemaid at age 4, and then being sent to boarding school at a very young age (ten), he investigated parent-child attachments and came up with some valuable observations about the importance of the parent-child, particularly the mother-child connection, that emphasize the importance of a healthy dependable parent-child bond.
And Bowlby also made observations about the causes of mental problems, like when he spotted the root of one woman's extreme post-partum depression (she had violent urges toward her 6-month-old) was spending time with her mother. Finessing her mother out of the scene, along with other stuff I can't remember, led to the woman's healing and being able to form a warm and healthy attachment to her baby boy.
But again, even when the observations are accurate, the solutions may not be right or may not be right for everyone.
Furthermore, some of the experiments they conduct for these studies are a bit disturbing. Some involve showing children inappropriate images and some involve treating children badly on some level.
And some studies are faked, fudged, or shoved aside.
Researchers also like to search for the reason behind the normal human responses. This isn't necessarily a bad thing, but because they are mostly secular, this leads them down the wrong path into lots of theorizing (i.e. story-weaving) about so-called evolutionary necessity for such behaviors. (Even if you believe in evolution, you must admit there is no proof for their theories and no way to prove these theories. Too bad they don't look for the motivation somewhere else, like in the human soul.)
Good Progress, But Still Fumbling in the Dark
Yet again, the treatment failed. There is no official "cure" for personality disorders and treatment is unsure (except that people love Dialectal Behavior Therapy for Borderline Personality Disorder--and yes, it is helpful, but not a sure-cure). Dealing with such people is no easy trick either. So people were cautioned to create "No Contact" or "Low Contact" relationships with personality disordered people. Yet this also caused problems because "No Contact" is fraught with complications and sometimes, you can't go "No Contact." Well-intended "helpers" ended up harassing fellow victims by insisting, "Oh, just quit your job!" or "Just go No Contact and stick to your guns about it!"
This was until people started popping up and saying "I can't go No Contact; this is my child's parent. This person is in my life whether I want it or not" or "There is no remotely feasible way to quit my job; I'm stuck with this boss for now, so what do I do?"
The whole personality disorder field also words things as if the personality disordered person is completely aware of how manipulative they are and are calculating every move they make. (This is sometimes true, but usually not. Their behavior is more instinctive and "feels right.")
This field also fumbles with regard to personality differences. Rather than realizing that even mentally ill or very bad people still have talents and areas of incompetence, likes and dislikes, and all different temperaments, experts simply divide everyone into a different type of personality disorder: narcissist personality disorder, masochist personality disorder, passive-aggressive personality disorder, masochist passive-aggressive personality disorder (I'm not making this up), borderline personality disorder, and so on.
More recently, they've taken to acknowledging personality types by labeling extroverted narcissists as overt or exhibitionist narcissists, and introverted narcissists as covert or closet narcissists, and especially mean ones as toxic narcissists. This is a step in the right direction, but it is still not the whole tamale.
So again, the observations are helpful, but treatment and solutions are still up in the air.
Picking & Choosing Based On...?
Yet Psychology 101 never even mentions him and his work is hard to come by, even though his success rate was so high. I took psychology and sociology in college, read the latest bestselling psychology books (like Susan Forward and John Bradshaw), yet never even heard of Dr. Glasser until I was well into my thirties.
So this is another problem, that people aren't learning about methods that actually work. (Just for knowing, Reality Therapy mirrors mussar on several points, but it veers off with an emphasis on a person's relationship with people and not with God).
Furthermore, important studies can be ignored, even by respected publications. This has been particularly true in the field of psychiatry, in which certain medication have been shown to either be harmful or ineffective in most studies, with only a minority of studies showing it to be helpful. And based on those minority studies, psychiatric journals will hail that medication and psychiatrists will prescribe it.
I personally know people who went through therapy that they claimed to have found helpful, yet they still display appallingly bad middot. One even enthused to me about the emotional maturity she developed through therapy, which shocked me because I always thought of her as one of the more emotionally immature people I've met. I was like, Oh my gosh. If this is how you are now, how much worse were you before?
Even more common, I've met tons of people who felt helped by therapy and do feel better, but don't behave better -- or not much better, anyway. One young woman credited her expensive and highly recommended therapist with saving her life when she was suicidal, but this same therapy over the long-term still did not stop her from drinking, using hard drugs, rampant promiscuity, and treating some people badly.
One of the big draws of therapy is feeling validated, feeling like you're doing something to help yourself, and having someone there who compassionately listens to you. This doesn't mean that it helps as much as people like to think.
Of course, I also know people who were greatly helped by psychology, but there's always a limit. The deepest & most important work can only be done by ourselves (and this is something that the truly effective therapists are the first to acknowledge).
So in conclusion: Yes, therapy and the field of psychology can be helpful. Yes!
But ultimate solution is to turn inward and upward: to your soul and to God.
Dialectal Behavior Therapy Self-Help - (Maybe you want to understand more about it, which might seem funny after I've said that nothing beats classic Jewish mussar, but I'm all for transparency and doing your own research. It does incorporate several core Jewish mussar concepts like prayer, giving the benefit of the doubt, and zehirut/bechinah/mindfulness. But you'll see it's still missing that emuna connection.)
Six Reasons Why Logotherapy is the God-Fearing Person's Therapy of Choice - A guest post written by a frum logotherapist, logotherapy comes very close to Jewish classic Jewish mussar (maybe even closer than any other type of therapy?), but I have no idea of its rate of effectiveness.
Where is Modern Psychology Taking Us?
Why You Need to Dig for the Treasure Hidden in Your Own Backyard