yep - it can still be abuse even if the perp is the same age. the required factor is that there must be a significant difference in power between the perp and victim - in size, strength, authority, age, number (as in a group,) status, or experience. sounds like you qualify on the "experience" factor.
i experienced abuse that fit each of the above categories, but for years i denied that the same-age experiences were abuse. first i just called it bullying - because it involved a group and most of them were my age or only a little older. (like you, some of this was in a Scouting context.) but it looked like abuse and sounded like abuse and felt like abuse and its effects were the same as the actions of older, bigger, stronger, authoritative adults - that i knew were abusive. eventually i had to face that.
you might have some competition here for your title of "Dissociative King of the World." lots of guys here can relate to that.
anyway - well done, starting to tell your story. hope you'll get the kind of support and encouragement that i have found here. PM me any time if you want to trade war stories and aren't ready for the mass audience.
"That you are here - that life exists, and identity; that the powerful play goes on and you may contribute a verse. . . What will your verse be?" Robin Williams as John Keating in "Dead Poets Society"