I'm so sorry you have to go through this. I don't know yours or your boyfriends situation but my son is my addict, he started with percocets, then oxy's then heroin.
Thats the opiate road. (in case you didn't know vics, percs, oxys and heroin are all opiates) heroin being the cheapest to buy thats why addicts end up using it. It doesn't really matter if those drugs your found are heroin or coke, addiction is addiction no matter what the drug.
Now, there's not much YOU can do, this is his addiction, he can't quit for you, he can't quit for his children, or his job or his house. He has to quit for HIMSELF, HE HAS TO WANT TO NOT DO DRUGS OR DRINK. Thats just the way it works. There has to be a rehab and there has to be a program that he follows for the rest of his life. Thats just how addiction works. I don't know of anyone that has quit on their own and with no program to follow. Addicts who are"recovering" cannot socially drink or just do drugs occassionally. It just doesn't work like that.
I hope everyone here has given you some insight.
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You will find support here and noone will judge you for any decision you make.
good luck