I certainly can relate to this, especially on the issue of arguing. I'm not so sure being close to a break-up or being in bad terms makes sex better, but arguing certainly has an increasing effect on the sex life. My bet is that it has something to do with hormones, maybe, or generally that anything will do to work off the aggressions. Some do sports then, chop wood or kick lamp post, but sex ist just as much a physical activity.
With one of my two long-time relationship partners this has been an especially defining effect. Every time after we had quarreled about something, the slightest physical contact lead us to sex, and not really the tender kind. I'd say it was a special form of a fight, we were very competitive in bed then with lots of scratching, biting and thigh locks, and twice made motel beds break down completely. However, that fuck was usually what it took to clear the air, afterwards we could discuss a lot clearer and with more reason and ratio than before.
Is it me or does it get more sexual with your mate when you are on bad terms, arguing, fuck even close to the end? Today I argued and it feels like its over, yet afterwards I just wanted to relieve the tension with a bang. Since its long distance for us I ended up having phone sex with someone else and it felt so good, especially since I didnt physically cheat. Anyone go on a sex craze after arguing or even worse, ending it with someone?