If someone apologizes to you for wronging you, but you either suspect or believe that their apology is insincere, what should/must/may you do in response?
Is saying you forgive without actually forgiving (assuming you can't yet manage to actually forgive): Required/Meritorious/Advisable/Permissible/Discouraged/Assur?
How halachically necessary is it to actually abandon your grudge in this case? (Assume it was halachically impossible to rebuke them at the time.)
How might all this vary if you are, say, 40% sure that their apology is insincere, or 80% sure that their apology is 50% insincere, or 100% sure that their apology is 100% insincere?
If the halacha does not provide clear guidelines about what to do in such a situation, please discuss what is considered the most righteous and yashar course of action, ideally with sources. Thank you!