I'm not sure this is really on-topic, but I'll share it anyhow. I think it adds to your statement with personal experience.
Warning: This may be a bit long and hastily written.
For reasons, I once doubted my sanity. To make a long story short, I used to use an obscene amount of drugs. I'm an addict in recovery, sort of - I take prescribed Suboxone.
I didn't use because I didn't feel well, I used because I wanted to feel even better. I was never a stereotypical addict, I was a functioning addict. I had no major trauma, no abuse history, or any history of mental illness.
I used because I liked being high. I wasn't escaping anything. My life was fine. I just liked getting high. My drug of choice was opiates, they helped me sleep and not think all the time. In fact, I have a Ph.D. in Applied Mathematics - from MIT. I have plenty of money, healthy relationships, and no real criminal record, or at least convictions.
So, after rehab, I doubted my sanity. I doubted whether or not I was sane. I mean, what sort of sane person wants to shut their brain down and get high? What sane person knows the risks of addiction but still chooses to inject themselves with untested drugs purchased from shady people?
So, I went to the shrink and we had a few sessions. I did my best to be absolutely honest with them. Even during the peak of my drug use, I was completely honest with my physicians. They are tasked with saving my life, I shouldn't lie to them. I did the same thing with the head doctor.
Finally, he sets me up for advanced and expensive training. It was three eight hour days, one of which was spent taking this giant test called something like the MMPI. It is one of those tests where you fill in the ovals and it's thousands of questions long.
Two of the days were spent talking to people and doing some writing. They didn't feel obligated to hook me up to any of the machines.
It took a bit for the results to come back and it turns out, I'm not even remotely insane. I kind of hoped I was, because then I'd have a reason for some of my choices. Nope... I'm probably more close to clinically sane than the people who administered the tests.
Except, and this is the important part, they won't tell you that you're sane. This isn't verbatime, but it went something like this, "You show no signs of your life being negatively impacted by any diagnosable mental illness. You exhibit no significant traits of any clinically diagnosable disability as defined in the DSM-V." It was something like that.
So, even after all those tests, and apparently being pretty damned sane, they still wouldn't call me sane - only that I wasn't able to be diagnosed with anything on the list and that my life wasn't being harmed by any uncontrolable brain functions.
That's as close to sane as they appear to admit. The initial head doc hadn't done the tests, but had sent me out for them. We both got a good chuckle at the responses.
He then recommended I visit a therapist once a week and offered me some sleeping pills.
At the very least, they do seem inclined to keep you in their care. They won't say you're sane, either. Even when they couldn't pinpoint an issue, they still wouldn't say I was sane. The closest they came was saying that I'd no signs of my life being harmed because of a mental process I couldn't control.
Go figure?