Do not reward bad behaviour.
Sometimes it is difficult to recognise bad behaviour. It can be presented to you as a call for pity or empathy. It can be disguised.
You can tell good from bad behaviour partly by the intentions of the person claiming victimhood, are they virtuous?
Or are they hypocritical? Would they offer you their empathy in a similar situation or are they only in it for themselves? Maybe they just want to get one up on you? Use your empathy against you.
In any case, when you encounter bad behaviour:
If you can not ignore it then condemn it.