meaning in context - Is there an idiom or saying for an act that on the surface appears extending the olive branch but in reality it means to abscond responsibility

A couple of us have been trying figure this out.

Two parties have a conflict in a form of a proven betrayal that has come to an impasse so both remained conflicted. Then one party extends what appears to be an olive branch along the lines of "you have your view, I have mine. Let's just look forward". This is done with the knowledge that the other party will not be civil unless the conditions of the impasse are lifted allowing for the party that attempted to appease, albeit insincerely, to say 'I have tried but its the other person not wanting to be friends so I wash my hands of this problem.'

My friends and I have used 'Clear the air', 'Bury the hatchet', 'Sweep it under the rug' but it doesn't meet all the criteria stated. Does anyone know.

Answer

What you want is something along the lines of "Let's agree to forgive ourselves my trespasses"—but I don't know of any idiom in English that expresses that particular sense of mutual magnanimity toward one party's misbehavior. The closest one may be let bygone be bygones, which Christine Ammer, The American Heritage Dictionary of Idioms, second edition (2012) defines as follows:

let bygones be bygones What's done is done; don't worry about the past, especially past errors or grievances. For example, Bill and Tom shook hands and agreed to let bygones be bygones. {First half of 1600s}

Although this expression is neutral as to where fault lay in the original source of conflict, it doesn't require that both parties have been at least somewhat at fault. Still there is an implication that the grievances were not all on one side. More strongly suggestive of fault on both sides is forgive and forget (often anachronistically expressed as "forget and forgive"), which Ammer defines as follows:

forgive and forget Both pardon and hold no resentment concerning a past event. For example, After Meg and Mary decided to forgive and forget their differences, they became good friends. This phrase dates from the 1300s and was a proverb by the mid-1500s.

In effect, the offending person in your scenario is telling the offended person, "Get over it." Here is Ammer's entry for that idiom:

get over ... 2. Recover from, as in I just got over the flu, or I hope the children get over their parents' divorce quickly. {c. 1700} This usage sometimes appears as get over it, as on a bumper sticker following the 1992 presidential election: "Bush Lost, Get Over It."

The flippancy of the bumper sticker example is perhaps even more annoyingly evident in a situation where a person at fault seems impatient for a return to the status quo ante, as though forgiveness were a right claimable under some sort of ethical statute of limitations.