Being reminded of bad behavior


I’m not sure how to get a different result in a case where I said something unkind a number of years ago, that I had forgotten about. Yesterday, a 3rd party related a complaint someone had about me saying something negative/mean to them. I do not remember it specifically, but believe it is quite possible I said that. I feel embarrassed and like a terrible person for having said something mean and I completely see how I could have felt that way too. Anyway, I guess my current model would be:

C: 3rd party reported person said I said something unkind and mean
T: this is all my fault
F: guilty/unworthy
A: frozen, ruminate on how I do not deserve positive future events becasue I’m a bad person for saying X
R: do not get a positive future

C: same
T: I cannot undo this
F: bad (sick to my stomach)
A: frozen, ruminate on how I have caused a negative impact in my life
R: I already have negative relationship with this person, so I’m not sure what my new R is, maybe do not build other relationships?

I have already tried approaching this person in positive ways. The person does not speak with me, so working backward from desired result to actions needed (apologize, share, caring, etc.) do not work.

Should my R be “a positive relationship” and not a positive relationship with this person, or repairing this particular relationship?