I'm wondering if they are even looking into the possibility that he meant to take too much medicine. It's a very morbid thought, and may be entirely off-base, but if he was in such considerable pain and was taking anti-anxiety drugs as well as pain meds, maybe he was ready for it to be over. That's not to say that every one who is in pain and taking anti-anxiety meds feels that way, but perhaps he did. Regardless, it was not the OP's fault.