Boyfriends Coke habit

I just don't know what to do I love him to death but he just cannot say no to it. He's got an addictive personality and he's so easily led I have tried reasoning with him and all sorts. Don't please say get rid etc but he habit isn't the person behind it and when he's not on it it's amazing but he cannot see what it's doing to us and himself I just don't know what to do. I literally love him more than anything and just want to help but he lies are getting too much and the only time we ever argue is over drugs. He's just gone out to get more after being in it all night it's 2am and we really can't afford it.