This song is basically. D-A-G-A repeated

Rhythm:
       D           A           Gm          A
E||----5---5-5---5-5---5-5---5-3---3-3---3-5---5-5---5----||
B||----7---7-7---7-5---5-5---5-3---3-3---3-5---5-5---5----||
G||*---7---7-7---7-6---6-6---6-3---3-3---4-6---6-6---6---*||
D||*---7---7-7---7-7---7-7---7-5---5-5---5-7---7-7---7---*||
A||----5---5-5---5-7---7-7---7-5---5-5---5-7---7-7---7----||
E||----X---X-X---X-5---5-5---5-3---3-3---3-5---5-5---5----||

You can play them barre..  Or open chords.  whatever fits your style best i guess....


Verse 1:
D A Gm A
D A Gm A
          D               A
Well it's tough to have a crush
         Gm                   A
When the boy doesn't feel the same way you do
          D               A
Well it's tough to have a crush
          Gm                     A
WHen your best friend breaks the news
   D                   D/Eb
Perhaps you'll find me feeling better
Em             A
   In a day or two
         D               Gm    A  D
But it's tough to have a crush On you

Assuming that for the D, you're barring, for the D/Eb, 
I just slide the index finger up a fret (x67776), 
and then slide up again higher to the Em (779987).

thanks