I understand the existential crisis, I've been where you are but I also wonder if your mind has been a little screwed up by the cult if you are finding no pleasure in life other than drinking and sex and see no purpose in anything. It could be your brain's become conditioned to everything being deep, meaningful and having purpose. Like you said you were always fighting to be good enough for the paradise.
How did we fight to be good enough? Generally it was by denying ourself pleasure and happiness in life and forcing ourselves to do boring stuff every week. So now you need to retrain your brain to enjoy what humans love. Wake up and smell the coffee, literally. Smell coffee and relish the taste, cook food you love, try new foods. Do things every day that make you happy and stop looking for big meaningful stuff while you get your brain's pathways to enjoy pleasure, every day pleasures. Sunsets, starry skies, newly mown grass, the ocean, the dawn chorus, the smell of roses, music, art, poetry, travelling to new places.
You may then find you are more content with getting up each day and enjoying life as a human being on a planet, living one day at a time and letting eternity take care of itself.