Oh lords mine is going to be all over the place. XD *fear* Whee languages!

Opening Credits:
"Song of Blue" - ASIAN KUNG-FU GENERATION

Waking Up:
"Billie Jean" - David Cook

Falling in Love:
"Close to You" - EXILE

Fight scene:
"Ashita Tenki ni Nare" - Younha

Breaking up:
"Time" - Ne-Yo

Getting back together:
"Do You Wanna Dance" - Dream

Secret Love:
"It Had to Be You" - Michael Bublé

Life's okay:
"專屬天使 (Zhuan Shu Tian Shi)" - TANK

Mental breakdown:
"Tango: Maureen" - RENT Soundtrack

Driving:
"True to Your Heart" - 98° and Stevie Wonder

Flashback:
"Fire!! - Boy's Version" - Digimon Memorial Soundtrack

Partying:
"Inochi no Riyu" - EXILE

Happy dance:
"すべてへ (Subete e)" - 19

Regretting:
"一個人流浪 (Yi Ge Ren Liu Lang)" - 飛輪海 (Fahrenheit)

Long night alone:
"Forward, my men! ~ TRY AGAIN" - Tenimyu (Advancement Match Rokkaku) *cracks up*

Death scene:
"遥花 ～はるか～(Eternal Version)" - melody.

Ending credits:
"Ji Mo Rang Ni" - Eason Chan

And it was just as strange and all over the place as I thought it would be. XD