How convince boyfriend stop using drugs?

He has issues

He was ex addict

And now sometimes he does it

Like once in a week

I dont know anymore what to tell him

I've no idea

I read a lot a lot of psuchology and help for addict people couples etc

But he won't listen he says he controls it and can stop when he wants

Says he just likes it

What to fucking do?

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+1 y
He is great person
And i won't leave him
How convince boyfriend stop using drugs?
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