Lyric discussion by chiefgeronimo 

I think the lyrics are about a dog and its owner talking to each other. Hear me out. The dog is passing away and both the owner and the dog are comforting each other.

The first three verses are told from the perspective of the owner:

"Someday A white light Will come for you To comfort you

(Owner is telling his/her doggo that the "white light" i.e. death, is coming to "comfort" him/her)

Well I'll put My shades on To shield my eyes Yeah, that's what ill do And I'll face the light with you"

(Even though the owner can't bear to see it (shield their eyes with shades), the owner will face the light together with his/her best friend and comfort the dog to the end.

***The rest of the song is mostly told from the dog's perspective.

"Someday, you'll get, older I'll be right behind you New days, hard to, shoulder I'll be right behind you

(In the Chorus, the dog is telling its owner that even though you'll get older, I'll still be there for you in spirit. Even on tough days, I'm with you.)

Dog: Wait for me, ohh, cause I'll be right behind you Owner: Wait, and see, ohh, you know that I will find you

(In the second chorus, the dog telling the owner that he/she will have to wait a bit longer before they see each other again, so "wait for me". The owner then tells the dog, "when I get older and pass away you'll be the first thing I find up there in heaven."

Someday You may Forget me Well that's okay with me

(The dog says that even as time goes on and you forget me in the daily hustle and bustle of your life, that's okay, because we're best friends and I understand.)

Yeah, that's ok I'll see that you may Cry a tear for me Cry two or three And you'll face the light with me

("I'll see you that may", may refer to the dog coming back every year in May (possibly the month the dog died) because the owner will remember the anniversary of its death and the dog knows the owner will cry two or three tears for it. Then the last line is the opposite of the owner's line earlier that says "and I'll face the light with you", its the dog telling the owner I know you'll stay with me here at the end and comfort me.

[Chorus]

You had That feeling For a while now For a while now

You had Been feeling For a while now Let it slide now

(This is the dog telling the owner that he/she acknowledges the owner's emotional struggle while the dog has been deteriorating, unable to accept his best friend's inevitable death. Then the dog tells the owner "I'm leaving now, let it slide [let those feelings go, my times up but it'll be alright]" )

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