Some people just can't be dealt with intelligently. Seems like you tried and it didn't work. I like Madisgram's idea about writing it out. An argument, or any uncomfortable situation will fester with me because of all the things I wish I'd said or done...but didn't.
I've carried a lot of guilt about one particular family member that I think I truly hate. That's when I first started reading self-help books some 20 years ago...to try to fix me because those feelings must be wrong, right? I tried more than once to mend the fences but I just couldn't manage to master it. I finally reigned myself to the fact I still feel the same disdain for this person. Now I just avoid her. There are so many people I
do like....I'm not going to beat myself up for this "one" that I don't
I hope you find peace....