First off, tune your guitar a half step down (E flat, A flat, etc..)
Note* all of the chords here are how you should position your hand on a tuned down 
not the actual notes, G=G flat, C=C flat etc..

intro:
G (hammering on and off of the 2nd fret of the high e string
C (hammering on and off of the 3rd fret of the high e string
Then slide up to the 7th fret of the high e
and then drop back and play 2nd fret, 3rd fret, 2nd fret, open(on the high e)
repeat (1x)

1st verse:
(G)                                  (E minor)
Lonely road, we gotta walk it just a little bit farther
                           (C)                  (G)
Heavens knows it can't get any harder than it is today
(G)                                   (E minor)
Lonely road, it's not ahead but is it getting harder
                           (C)                  (G)(hammer on & off 
on E)
Heaven knows it can't get any darker than it is today
           (G)     (D)        (A minor)
Who do you miss in times like this
           (C)                     (A)            (D)   (C)
When your thoughts are filled with sadness and regrets?
              (G)              (D)       (A minor)
To who do you pray when you've lost your way
           (C)
And you've such a heavy load?
       (B flat)       (C)              (D)
Let me walk with you upon this lonely

(D,D,D,D,D) (C,D,C,D,D)
road

Then slide up to the 7th fret of the high e
and then drop back and play 2nd fret, 3rd fret, 2nd fret, open(on the high e)
repeat intro (2x)

And that's it for the guitar chords, they just repeat in that order little to no 
Listen to the song for a better account of the progression, but otherwise you should be all set 
this + the rest of the lyrics below.

2nd Verse
Lonely road, empty kitchen and a brand new feeling
Nothing's moving but my heart is reeling since you went away
Lonely road, gotta walk it till we start forgiving
Find another way to go on living without you today

Chorus
Who do you miss in times like this
When your thoughts are filled with sadness and regrets?
To who do you pray when you've lost your way
And you've such a heavy load?
Let me walk with you upon this lonely road

3rd Verse
Lonely road, we gotta walk it just a little bit farther
Heavens knows it can't get any harder than it is today
Lonely road, gotta walk it till we start forgiving
Find another way to go on living without you today

Chorus
Who do you miss in times like this
When your thoughts are filled with sadness and regrets?
To who do you pray when you've lost your way
And you've such a heavy load?
Let me walk with you upon this lonely road