When writing any type of autobiography, treat other characters how you would like to be treated if they were writing about you.
It's a juggling act because you don't want to downplay your story by fudging the truth of how your grade six sewing teacher deliberately threw a box of pins on the floor and made you pick them up, but always be aware of the consequences of writing disparaging remarks about people who could take offense or, in extreme cases, legal action, against you. And think about their offspring as well.
When you write any form of memoir you have the opportunity to show your evolution throughout your story; your other characters do not, so don't tell the part about how Stretch Nordmeyer fell and damaged his .... while streaking through the caf, without first asking Stretch how he feels about this incident being made public after all these years.
Also try not to use an autobiography as a revenge platform (I’ve seen first hand how this plays out and it’s not pretty) for that will probably come back to bite you one day.
Telling the truth about those honest-to-goodness baddies in your life may require a few creative writing skills, but it can be done with integrity and flare, leaving you proudly perched on the high road.
In real life stories, be aware, and handle your characters with care.