my ex's family used to make lots of negative comments about our coffee habit...cuz caffeine is soooo bad. But then they turn around & have tons of chocolate and Mountain Dew....Mountain Dew has as much caffeine as my coffee, enough so the higher uppity people in their church gave them a lecture about it, but they still drink it.
I think you drink too much coffee. It's just not good for you to have too much of anything, but I have heard that 1-2 cups a day is actually good for you. Decaf wouldn't help your budget either, since it costs more. Maybe you could just cut back? It could also be a major reason why you don't get enough sleep. Have you tried some of the less expensive brands? If you find them bitter, try adding a pinch of salt to the grinds in the basket.