Sling Blade Friendship Quotes

How we cite our quotes: All quotations are from Sling Blade.

Quote #7

KARL: I'm tired too. Just 'cause I ain't gonna be around no more, maybe that don't mean I don't care for you. I care for you a good deal. I care for you more than anything else they is. You and me made friends right off the bat. […] It don't make no difference where I was to be. We'll always be friends. Can't nobody stop that.

This is Karl's way of saying goodbye to Frank. Is he being a good friend to Frank by killing Doyle? Or would he be a better friend to Frank if he stayed by his side literally, instead of with all this metaphorical "we'll always be friends" stuff?