Having had my own experiences with this, I think this is about having a family pet that dies - "had to say goodbye to the fuzzy little guy" that is on medication - "they said the meds will take care of things for me" which aren't working. and you have to watch it get weaker and more tired day after day while the idea of it being gone some day is literally haunting you - "today I felt scared thinking of your empty bed".
yet you don't really want to accept it - they've lived that long, who said they couldn't for even longer, right? - "but I know you'll be fine, yeah you've got to stay alive"
it is the last song I played for my cat, the evening before she was put to sleep and to this day it's the only thing I can think of when listening to it. the album cover makes it even worse.