There's a difference between targeting and rivalry.
If I were to
target Huahwi, I would
target him off spawn and follow him server to server incessantly.
Whereas my
rivalry with him is because I feel he threatens my existence as a small Youtuber and competent player, so even though I don't follow him between servers and kill him off cornucopia repeatedly, if I see him in a game, and we just so happen to be fortunate enough to cross paths, I always try my hardest to kick his ass six ways to Sunday.Granted, that usually doesn't happen because (and this is the only time I'll ever be caught dead saying this) he's actually (SO FAR) better at PVP than me (though my craptop and lack of Optifine also plays a significant factor).
There's a difference between healthy rivalry + wanting (dreaming of) revenge, and harassment/targeting. I believe the song "Walk the Line" by dear Johnny Cash is in order here.