I'm a metalhead for the total different reason than you, it is because i am open minded.
I do also love other bands that aren't metal, but have that 'darkness' and emotion to them, like The Tea Party, or Days Of The New...
Yeah, i'm a true metalhead, but i'm not of a closed mind, i listen to anything from MARTYR (ha ha, you were waiting for it metalized) to Morbid Angel, Vanishing Point, Iced Earth, Testament and Dragonlord, Cynic, Dream Theater, Megadeth, Nevermore, Metallica, Meshuggah, DEATH (rest in peace, freind...)... etc.
Awesome music, Awesome musicianship, Awesome Lyrics, Heavy as ALL FUCKING HELL/dark as ALL FUCKING HELL... These are what make the many genres of METAL my favourite style of music