To Your Health Lyrics
Here's to you, you old wreck
And mine is a thorn in the side
Drink up, so we can both finally die
With nothing to row
With nothing to row
Here's to you, you miserable fuck
And why did you finally leave?
Because all you think of is me
Because all you think of is me
To your health
Here's to you, you old wreck

I'm pretty sure the correct lyrics are:
Make mine a pain in the neck Here's to you, you old wreck And mine is a thorn in the side Drink up, so we can both finally die
And I'll have a bright yellow boat With nothing to row With nothing to row
So make mine an all out of luck Here's to you, you miserable fuck And why did you finally leave? Because all you think of is me Because all you think of is me
Make mine a pain in the neck Here's to you, you old wreck

the part about the boat implies he has no direction and nowhere to go now he is alone.
Pain in the neck could mean he is feels annoying, like the saying if someone is a pain in the neck.
The song is basically about him being left, and not knowing what to do with himself imo

I think the second verse starts "make mine an ore out of luck" referring to the boat with nothing to row.
This song is deep and one of my favs, I feel he is talking to himself, hating himself for losing his love. When he says "why did you leave, he answers himself by saying because all u think of is me. I think that's his way of saying he lost her because all he did was think of himself. The last line in the first is him wishing for death, for a release to the pain. "Drink up, so we can both finally die"
Just my thoughts and my interpretation, would love to hear others thoughts on this song

This song almost strikes me as someone dealing with alcoholism and almost conversing with the demons inside him. Losing the love of his life, the lines stating "why did she finally leave, cause all you think of is me" would be him speaking to the alcohol. The boat line shows he is directionless, all he can think about is his next drink. That, and "To Your Health" can be a common thing to say before taking a drink. Just my thoughts anyway.

It seems to me that this song is basically about the aftermath of him being left. He is drinking in a metaphorical bar, and I believe parts of the song are written from a somewhat different perspective, seeing as the lines "Drink up so we can both finally die" and "Why did she finally leave? Because all you think of is me" seem to be referencing multiple persons. I believe the second line there, the one which claims "Because all you think of is me" seems to show that it may be written from not a person's perspective, but from the perspective of part of his personality, maybe the part of him that is sad and lonely and scared. I'm not sure, though, all of this is my opinion. I think only Keaton himself really knows!

To me, it sounds like his addiction(I would assume alcohol from the references) speaking to him. Telling him he lost her due to it. Very powerful.

I think this song is about his addiction to alcohol and drinking. But to understand the whole meaning of it, we have to look at it, as he is talking to his mind and consince. He's struggling between his logical thinking and his needs and hunger. Make mine a pain in the neck" : He knows that being an alcoholic is not worthwhile. But asks his consence to make him guilty by having a drink. "Here's to you, you old wreck." - He hates himself that he couldn't resist. He considers himself as he was an old wreck. "And mine is a thorn in the side." His source of pain is a thorn in his side. He feels very guilty, and this is a metaphore for his sins. "Drink up so we can both finally die" He's drinking to erase his pain. He just want to have his addictive and die after that. Or another meaning is: If he's gonna die because of drinking, then his sins gonna be forgotten as well and he's not gonna feel guilty anymore.
"And I'll have a bright yellow boat" This is another metaphore. And it's about the meaning of colors. In color psychology, yellow is the color of the mind and the intellect. It is optimistic and cheerful. So this boat means his hope to have a better life. When he's gonna be fine without any pain. "With nothing to row" He's hoping that someday he's gonna be fine, but doesn't know how to make the first step. He's lost and doesn't have the strength to change. "And why did she finally leave?" Okay, so in this case "She" means the boat, not any girl or lover. So this phrase actually means that he lost his hope forever.
"Cause all you think of is me" This is about the addiction itself. He couldn't make the change, because he is addicted.
And to make the whole song and message more painful he finishes with this sarcastic, sad sentence: "To your health!"
He accepted he's not gonna change.
"So make mine a pain in the neck. Here's to you, you old wreck."