Letting go of bad past situation

I had a situation at work about a year ago. Accused of something, investigation and there was “no finding” of any major issue. It still however haunts me as many people are aware of it and I feel the “cloud of shame” over not recognizing the issue earlier and dealing with it directly so that it never would have gotten to the place it did (I was distracted by other major items – there was a lot going on at the time). I am in a place where I could retire and just remove myself from the situation/daily reminder. The trouble is – they don’t want me to do that …they actually want me to stay. So obviously they believed in their finding and believe I have value to add. But I’m angry at them because I received no apology and feel like I am “damaged goods” now.
How do you really let go of “shame” around an experience where you were perceived to be part of the issue versus when someone else does something negative to you? Most of the posts I see on this site are more about the latter versus the former.