It's wasn't his fault. Not completely. It wasn't his fault when Percy got onto the councel, Ignoring Him,
pushing him to the side. It wasn't his fault he went on that expedition only to lose Sky in that miserable ice storm.
It wasn't his fault he came back to cybertron with gaps in his memory processer!
He had traveled back after Two Vorns of searching, half offline from energon lose!
It wasn't his fault when he went hurting, aching, Needing his other half,
only to have him accuse him of murder Just Like them! It wasn't his fault.
So when the war started, Really Started, not just the riots, He shouldn't have been surprised when he joined the Decepticons, When he helped masacre the other councel members whom ordered Vos destroyed, when he offlined other mechs without mercy, When, thousands of years later and on the battlefield, he saw Sky with an autobot symble, and Shot.
Really, It should have been expected. Theres no need to cry over spilt energon after all.