I interpret this song as Ed feeling like he's becoming "far-gone," putting himself in a corner that he was concerned about getting to. Maybe filling up a void with alcohol, probably not to the point of being an alcoholic but using this as a way of escaping his depression? The bridge I think either is talking about the temptation he's facing or self-harming. He has the line "This is when it ends, I feel the chemicals burn in my bloodstream." This is when it ends, comes off as his final thought on his growing hopelessness. However, he has "Lord forgive me for the things I've done" is actually a pretty hopeful line. I'm sure it was written with the self-deprecation, but instead of the "Lord hit with the deserved lightning bolt" but more of a loving "I hope your holding out your hand God." Actually probably a mixture of both. Nevertheless, Ed accidentally wrote something of hope in his song of hopelessness.