I think you all have set a good understanding thus far. Two things to add:
First, the title of the song. It is not, “someone Like You” as one might expect. No. It is “Reason to believe.” An odd title to say the least. Why call it that instead of the much more catchy, lyrical “Someone Like You.”…I mean, it is a love song, right. The problem is exactly with this “Somone” who is like the way she is…assuming the singer is male and his love is female.
Ok…so what to think of that? He loves her, that is clear. First two lines…if I listened long enough to you, I’d find a reason to believe that it’s all true." We believe the ones we love. Until so much too late often. So, that the title of the song is Reason to believe, screams to us that there is reason not to believe…though he admits he doesn’t see it…and if he starts to see it, he is only one long talk with her from believing again. He Wants to believe her!!! Even with her now clear lies, that she doesn’t confess even though he cries (sounds like he says cry, not Cried, as we might expect!)…causes him great anguish. She doesn’t care a flip. He sees it. And yet, "Still I look for a reason to…to what…to believe. " Why? That would keep he and she and the love (based a lot on trust) alive and together…he still looks for a reason to believe.
It’s the name of the song. It is the point of the song. He has reason to not believe…he looks for a reason to believe.
And apparently, no reason will be forth coming.
SLY = Someone Like You.
But here is the second thing. The chorus lines. The memorable part of the song…and the reason we don’t pick up on the first thing very well. It is oddly worded to us. And maybe time and country hasn’t helped us undrrstand. I agree with one post earlier post that the line, “someone like you, makes it hard to live without sombody else” to me it almost sounds backward…it is suppose to be a compliment, parallel to the second line “SLY makes it easy to give, and never think about myself. " both are compliments. Second one is easier…it means that this lady is so wonderful (in what ways we are not told due to the problems now at hand) that all he thinks about is pleasing her. What a great, great love! He doesn’t think about himself. It’s like the old song, Byou are everything and everything is you.” And if you haven’t had a love like that, you haven’t lived long enough. 
so he loves, loves loves her. So the first line of chorus (as stayed by another) is "SLY makes it hard to live without somebody…any somebody. …else that will be as wonderful as my love for you. To leave her will place him in an empty void. It is so empty he cannot imagine it. And she is so wonderful (aside from this tragic new understanding of her real character) that he cannot stand to think of living in the void of emptiness again.
He can’t leave her…not without someone equally as wonderful. Both strong compliments…sad, because they are based on a misunderstanding of her, we know. But what was my second point?
The chorus line changes. I’m shocked how few people notice it.
The chorus lines are sung twice…after a long musical thinking period…he sings the chorus agsin, but he changes the words! Why?
see, we after that first part of the song, we are left to wonder…will he leave? Or will he stay because of love? Or will she just talk him into staying as he fears?
Musical bridge and we are dropped directly into the new chorus…which now sings:
SLY makes it EASY to live without somebody else.
What?! He changes it?!! Now it has become easy to go? Why? Knowing… you know the lyrics. Do Back To The Chorus. Look again.
SLY makes it EASY to live without somebody else.
SLY makes it HARD to give and never think about myself. (When someone harms you greatly, you self protect…now it is clear. He can’t keep giving to her. And further, leaving will be somewhat easier when he can recall her true character.
Got it? Now he is leaving. Now it is easy. Why? Knowing that you lied…not in some silly unimportant way…knowing that you lied STRAIGHT-FACED while I CRY. It’s the lie, with no remorse, no reaction to it, though she sees him totally destroyed over it. It demonstrates zero care. And after our musical interlude, he sees it for what it is. He changes the chorus lyrics and determines to live without her. Done? Not quite. Repeat opening lines eaxctly. He doesn’t quite trust himself.
Recall his cunundrum? He loves her and can’t live in the emptiness of the loss of this love…so even though he is leaving he still “looks for a reason to believe.” The mornful loneliness sets in. Blues at its best.
