Well, that was pretty much the theme of the episode... I saw it a few nights back so it should STILL be fresh.
Anyway, Man E. was ostracized by society because of having a beast face and a human face, wound up becoming a loner, and had no where else to turn. He wound up going to the Hobbits... arggh Widgets (they look SO much like refugees from an unsold Lord of the Rings pilot) and pushing them around for food and shelter. Skeletor watches this from his 1980's cartoon bad guy "I can see EVERYTHING" device, abducts him, pushes him around for his abilities, and has Beastman take total control of his beastly half.
So basically, Man E. winds up getting a taste of his own medicine and repents after the He-Mensch saves him. he then becomes the most famous actor in Eternia.
So basically the THEME of the episode is not only is bullying bad and not to wind up passing that on to someone else, it's also that sometimes people are nasty because no one reaches out to them.
So here's the moral I'd see:
He-Man: In today's episode we saw that Man E. Faces was constantly bullied, leading him to become one himself. Now, in real life, I can't just come over to help you by stock animation punching someone in the face. Bullying is a vicious cycle, and if you find yourself in the same situation, there's a sure fire way to have that cycle end on you. Just be passive aggressive. Take all the crap everyone gives you with a smile on your face, and come home and complain about it to your friends, your family, even out loud to yourself. Remember, if you call those guys hog faced sexual deviants to their faces, they'll rip your lower intestines out... but doing it in private to no one that cares works just as well.
(Yeah, I'm half joking... but that very advice kept me out of fights and or more violent actions)