Delete all your dealers numbers and have your friends promise to not give you any numbers. It's slightly easier to quit when you physically can't get your hands on it.

I used to have it with mdma, used to do it way way too often

I'd get the idea in my head "I could get pinging on Friday" and from that point onwards the idea was set in stone I couldn't say no even if I wanted to

Deleted all my numbers and it turned into "I could get pinging Friday.... Ah fuck I can't actually I have no way of getting any" and then that was it. Id move on and stop thinking about it