Angst, it's always in stories. You see it while a character is pacing up and down a room pulling their hair out over what seems like an impossible impending desision. That's angst.
When the two main love interest characters are in their "I hate you!" "I hate you too!" stage of their relationship, which can be seen in any Mills and Boon book, while their lust for each other bubbles away under the surface; that's angst.
Any kind of heated argument: Angst.
Here are some of my favourite songs for writing theses gritty parts of stories:
Blood On My Hands - The Used
The little goth girl in me still loves these guys.
Psycosocial - Slipknot
Pretty heavy, even for me. Although I'm told this is 'light' by their usual standards!
Love The Way You Lie - Eminem ft. Rihanna
Really can't get enough of this at the moment. Brillant piece for when one of your 'bad' characters is a bit of a masochist.
Make Me Wanna Die - The Pretty Reckless
Kick ass is an epic movie. Taylor Momsen gets some crap but I think this is an awesome song.
Taking You Down - Egypt Central
My cousin introduced me to these guys and I just love their music!
Bury Me Alive - We Are The Fallen
Evanescence wanna'be's but still, I quite like this song.
Going Under - Evanescence
The original Queen of Angst. Amy Lee is a legend.