Quite a sad song indeed.

>means strum a whole bunch 

Verse (Wait for the guitar) "You're sitting with your best friend..." 
G|---------------------------------------
D|---------------------------------------
A|----------4>------2>-------------------
E|--0>--------------------2--2-4--4-5>--- 
play that as needed 

Chorus "And i'm still here..." 
G|----------------------------------------------------------------------|
D|----------------------------------------------------------------------|
A|---------------------------------------------------------2>------/6---|
E|-2-2--2-2--4-4--4-4--5>--------------2-2--2-2--4-4--4-4---------------| 

Play the verse, then the chorus again, and then here comes the cool part 

The cool part at the end with the "Lock your door" sample (The timing is 
kind of tricky, just listen to it, you kind of follow the drums) 
G|-------------------------------
D|-------------------------------
A|-------------------------------
E|-0--0-0-0--0-0--0-0--0-0-0-0--- 
Play that 4 times, then 
G|--------------------------------------------------------
D|--------------------------------------------------------
A|----------------4-4-4---2-2-4--0--0-0-0--0-0--0-0-0-0---
E|-0--0-0-0--0-0------------------------------------------ 
Play that 4 times, then 
G|--------------------------------------
D|--------------------------------------
A|--------------4-4-4---2-2-4--0--------
E|-0------------------------------------ 
Play that 4 times, and end with an open A string