I last washed my hair with african Black Soap (my 'shampoo' of choice, customised for my hair needs) over a month ago when I took out kinky twists. Other than the occassional 'poo, I only ever co-wash. I do this everytime I DC which is 3x/wk, and my hair and scalp are both squeaky clean after a wash - no build-up at all. I apply stuff to hair and scalp daily too, oil included and no problems. I've customised my routine to suit me and I'm still customising, as I learn and incorporate new things, like ayurvedic practices.
I think you need to find a routine that suits you. I rarely use condish straight out of a bottle - I dilute a dollop in a spray bottle with either water, oat milk or herbal/ayurvedic waters and teas and spray it on - makes the condish last and it saturates my hair so well I have some left over for a rinse or for the next wash. If my hair's pretty dirty, I see the dirt washing away too - it works! But then again, as someone said, perhaps it just isn't for you. Try adding sodabic, maybe that'll help with the transition from shampooing.
Also, it's easy for people to think the stripped feel of hair after shampooing is clean, so anything gentler that doesn't strip as much makes peeps think their hair isn't clean when in fact it is. Try phasing the 'poo out gradually if you want to stop using it.......