When I hit my own rock bottom a couple of years ago I stumbled upon Jordan Peterson's lectures about meaning and the bible. It helped my rational mind understand and accept that the rational mind isn't the be-all and end-all and there is something transcendent outside of it. Whatever that is, you can aim at getting better at "dancing" with it and the better the dance the greater the sense of meaning. YMMV but it worked for me.
(the lectures were "2017 Maps of Meaning" and "The Psychological Significance of the Biblical Stories")
(the lectures were "2017 Maps of Meaning" and "The Psychological Significance of the Biblical Stories")