Damn, this really hits home for me. My brother got prescribed statins and one day the family had found out he'd stopped because he didn't believe in it and they didn't feel like they were doing anything.
He's one of the most scientific guys I know but began giving conspiracy theory/anti vaxx sort of answers of how you can't trust medical studies all the time. When asked why he still takes his hypertension meds and trusts the literature there, he couldn't answer and he said it's just a feeling. The family was pretty astounded. Honestly felt as if someone you know suddenly started believing antivax or say flat earth ideas is the closest way I can describe it.
I was explaining how inconsistent his thinking was, bordering on delusional. If the truth was that the statins affected him psychologically, I can see why he'd chose to hide it when his wife and parents are grilling him for it.