Do you know what it's like, for example, to want alcohol so much that even when you aren't drinking it, all your thoughts morph into it? Even though you're not drunk, you're never really sober. You can't snap out of it. You aren't actually taking a sip, but that's not enough. You should be steering your thoughts away from it.
Slap yourself awake. Get addicted to something else. Give your thoughts something else to cling to.