My fiancee works for an escape room and she is good at her job. All the keys go back where they need to, the rooms are always cleaned and put away properly before her shift is over and she has never had a bad review. Sometimes, something breaks or a key goes missing and even if she wasn't the one working, her boss automatically blames her. Apparently he has been talking about her to her co-workers about how he thinks she is incompetent and wishes he could fire her. Her co-workers know that these things are not her fault, but the boss seems unconvinced that she isn't incompetent.
We are not in a position where needing to look for a new job is going to be okay for us. There is no HR, the boss is the only guy in a position above her. If he fires her, she may be able to collect unemployment but it's just an all around annoying shitty situation. Is there anything we can do to retaliate? She is already an amazing employee and aside from continuing to do her job correctly, I don't know what advice to give her.