You might be up for this read (link below). Mine is quite a different approach with respect to Peterson's (the psychologist you're lauding on many posts, hope I did not misspell his name).

https://steemit.com/onemanyproblem/@apollonius/mere-tolerance-an-answer-to-professor-dario-antiseri-s-proposal-of-moral-relativism

He's okay, but I believe the best approach against relativism is to go straight to the absolute, then, of course, you have to show the frightened relativist that the absolute is not "scary", it is not "absolutist" or "tyrannical". It is no more "absolutist" than the bones are "tyrannical" to a living body.

But you will have to do some serious reading. The original print out of the pdf is 14 pages, so you can gauge the length.