When you have to close something, to put an end to something that's not making you feel good, you just gotta do it. Try to be fair and square, honest but resolute, and hopefully things will go better for all of the parties involved. I've had to say "that's enough" to things quite often in the last dew months and it's never an easy choice, realising (first) and then accepting that something is not making you better off and is not likely to even in the long term, taking the decision and (the hardest part), making it effective. That's the most difficult part when there are other people involved, but you gotta do what you gotta do, be it leaving a job, ending a relationship, saying goodbye to a place or else. Goodbyes and adieus are sad but inevitable, and even when you immediately feel happier and more relaxed, there's always this kind of melancholy that makes you sad for things not going the way you hoped for. That's exactly what this song is to me, the feeling it talks about and evokes.