It might not have been the original meaning but when you think of a cult member drinking the Kool Aid (that will kill them) they might be a true believer with no doubt in their mind, but they could also be someone who isn't sure but is being led by peer pressure ao on.
When you accuse yourself of drinking the kool-aid, (or discuss yourself drinking the kool-aid), it carries along a degree of self-recognition: "sure, maybe I'm drinking the kool-aid, but at least I realize it".
Thanks. Nit-picking again, but drinking the Kool-Aid does mean "unquestioning, ... without criticism" implying that those who are drinking wouldn't have such reservations. That's what I was confused about. Oh well. Language is evolving, what else is new.