This sounds like Ketamin addiction. The slurring, passing out into a K Hole, the nastiness. If it was cocaine you would have money issues by now unless you’re wealthy.
Ketamin is cheap hence why it’s so popular with the youngsters
The best drug tests are the urine dip tests if he will do it in front of you. You can get them on the Internet
I really feel for you but you’re far far from alone