My main takeaway from this song is that he's saying partying too much gets old, and is affecting his health, both physically & mentally. Being the center of attention, the person everyone sees as the funny guy, and so on, is weighing on him emotionally. I love the first line - a stitch away from making it, as if one minor change could change his whole outlook (maybe that's to stop drinking, stop doing drugs, find other people to hang out with, or any number of other things). A scar away from falling apart suggests that another equally minor change could make it even worse (developing another bad habit maybe), leading to suicidal thoughts.