Offered friend's job

Pinzy

She's not being told till next week, so even if she does put two and two together, there'll only be a few potentially horrible days. Don't worry about her complaining to other people, they probably are aware themselves of how she obviously hasn't been able to do the job. If she starts banging on on FB etc. about being stabbed in the back, just ignore it. She may be supported by some equally clueless friends of hers, but who are they to you? Nowt.

Worst case scenario - you lose her as a friend. As you said, she's quite erratic, and it's not like you've found the bestie version of The One. It's crap, but she'll live to lose another job.