I used to have a friend in high school who listened to metal (Metallica and Slayer mostly). Hated his taste. I was into electronic music at the time, and firmly believed that guitars are obsolete and will die out within a decade.
Then, one night in 1996 or 1997, I was sitting alone in a dark room, gloomy and under the weather, to say the least. The TV was on, and a song started to play. It gave me the chills. The kind where you immerse yourself into the music like a lucid dream. The song was Hope from Anathema, and I've been a fan ever since.
This changed my taste in music a lot, and I opened up to pretty much all kinds of music: I listen to metal, classical music, electronic, and so on and so forth. But metal has a sweet spot in my heart. We even had some metal playing during the dinner at our wedding.
To name a few favourites: Anathema, My Dying Bride, Theatre of Tragedy, Therion, Thy Catafalque, Gire, Blind Guardian, Rotting Christ, Cradle of Filth - and I could continue for hours.