You are not a bad person, speaking for myself, it just gets old. Waiting, watching, hoping, then having the rug pulled out from under you, over and over again.
If your boundry is "when/if" he drinks again, it's over, then that is what it should be, say what you mean and mean what you say.
Unfortunately, when one makes the choice to stay with someone who has addiction issues, the worry...never ends.