Why do you not want the guest back? Policy breaking? They 'dont' fit'?
If it's policy-related I would tell them outright. 'Last time you were here you smoked in your room. We did not charge you for that but we also do not wish to deal with the cleanup again, either. Here are a couple of other places in the area that have smoking rooms.'
They don't fit? 'Last time you were here we noticed you did not seem to really be enjoying yourself. Perhaps you would like to try these places, which may be more to your liking.'.
"she gets drunk every night, vomits, and disturbs the other guests by being overly loud"
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Exactly, Little Blue. That's pretty much enough already, the first time.
But it's happened more than once so it's a no-brainer. It reflects badly on the inn - and innkeeper - to have drunken and disorderly guests. Just not what your treasured guests are really look for. Not exactly ambiance.
Disturbing the other guests - every single time it sounds like - is reason enough to blackball this guest.
Would I tell her myself, that she's not ever going to come back?
Probably not. Drunks are not generally the most rational of people; trying to talk sense to them, even in the daytime may not be the best plan. And chances are not good that she's going to even admit her behavior - if she remembers it.
But I'd keep her out all the same.
How? Just whenever she wants to come back - and however often she may try - I'd stick with the old standby: Sorry but we just don't have anything available. I'd stick with that until she finally moves on and gets in the habit of staying elsewhere. And she will.
Recommending another inn for her is the only really tricky issue here. Dumping a disruptive guest on another inn/innkeeper isn't exactly cool. If there's a place nearby with stand-alone cottages and no opportunity for her to create disruptive noise, that might work.
Disruptive guests are a no-win for everyone. Keep them out. Your guests deserve better than that - and so do you!
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