This song is fairly straightforward - I've transcribed the chords for a single 
acoustic (or rhythmn) guitar. The C-Csus4 Am-Am6 G progression is played as 
follows - you'll have to get the timings by ear (probably the trickiest bit):

C (x32010@1)   Csus4 (x33010@1)    A (x02220@1)   Am6 (x02212@1)      G(2 (320003@1)bars)
e|----0-0-0-0-0---|----0-0-0-0-0---|----3-3-3-3-3-3-3-
B|----1-1-1-1-1---|----1-1-1-1-1---|----0-0-0-0-0-0-0-
G|----0-0-0-0-0---|----2-2-2-2-2---|----0-0-0-0-0-0-0-
D|----2-2-2-3-2---|----2-2-2-3-2---|----0-0-0-0-0-0-0-
A|----3-3-3-3-3---|----0-0-0-0-0---|----2-2-2-2-2-2-2-
E|----------------|----------------|----3-3-3-3-3-3-3-etc

Intro: C Em Am F

Verse 1:

C (x32010@1)The last time you walked away
                              EmYou (022000@1)left this weight with me,

It's in my heart it's on my back,
                         FI (133211@1)think it might bury me,

I wanna cast you out,
                           GBut (320003@1)that's just half of me,
                                                        C- (x32010@1)Csus4The (x33010@1)other half believes there's more to us than tragedy,

Bridge:

Am- (x02210@1)Am6 (x02212@1) GBut (320003@1)I can't do it on my own

Chorus:

C (x32010@1)       Em (022000@1)     AmOh, (x02210@1)oh oh oh, oh oh oh,
       FStay, (133211@1)stay, stay,
C (x32010@1)       Em (022000@1)     AmOh, (x02210@1)oh oh oh, oh oh oh,
              FOr (133211@1)don't come back if you walk away,
C (x32010@1)       Em (022000@1)     AmOh, (x02210@1)oh oh oh, oh oh oh,
           FI (133211@1)can't go on like it's all the same,
C (x32010@1)       Em (022000@1)     AmOh, (x02210@1)oh oh oh, oh oh oh,
         FSo (133211@1)stay, stay stay.

Verse 2:

C (x32010@1) Don't tell me you're not safe,
                            EmIt (022000@1)sounds like a dare to me,
                                                          FAnd (133211@1)if you doubt don't shut me out, that's not fair to me,
                                                        GI (320003@1)know i hurt you too, When I was looking for clarity,
                                                        C-Csus4
But all I know is when I go, I want you there with me.

Am- (x02210@1)Am6 (x02212@1) G (320003@1)               C-Csus4
'Cause I can't do it on my own,
Am- (x02210@1)Am6 (x02212@1)   G (320003@1)                                      CAnd (x32010@1)if I got you I think I could hold on, hold on...

Chorus:

C (x32010@1)       Em (022000@1)     AmOh, (x02210@1)oh oh oh, oh oh oh,
       FStay, (133211@1)stay, stay,
C (x32010@1)       Em (022000@1)     AmOh, (x02210@1)oh oh oh, oh oh oh,
              FOr (133211@1)don't come back if you walk away,
C (x32010@1)       Em (022000@1)     AmOh, (x02210@1)oh oh oh, oh oh oh,
           FI (133211@1)can't go on like it's all the same,
C (x32010@1)       Em (022000@1)     AmOh, (x02210@1)oh oh oh, oh oh oh,
         FSo (133211@1)stay, stay stay.

Solo:
D Am D Am D Am F C

Bridge:

C-Csus4 Am-Am6 G    C-Csus4

Am- (x02210@1)Am6 (x02212@1) G (320003@1)               
'Cause I can't do it on my own,
C~~
Oh, oh oh oh, oh oh oh,

No-oh-oh-oh

Oh, oh oh oh, oh oh oh,

Or don't come back baby

Chorus:

C (x32010@1)       Em (022000@1)     AmOh, (x02210@1)oh oh oh, oh oh oh,
       FStay, (133211@1)stay, stay,
C (x32010@1)       Em (022000@1)     AmOh, (x02210@1)oh oh oh, oh oh oh,
              FOr (133211@1)don't come back if you walk away,
C (x32010@1)       Em (022000@1)     AmOh, (x02210@1)oh oh oh, oh oh oh,
           FI (133211@1)can't go on like it's all the same,
C (x32010@1)       Em (022000@1)     AmOh, (x02210@1)oh oh oh, oh oh oh,
         FSo (133211@1)stay, stay stay.

Outro:
C Em Am

Enjoy!