Drambuie is one of those things that hangs around the house for a long time looking for a good use, or at least that's the case in my home. I'm on my second ever bottle, the first bottle originally belonged to my mother, it lived next to the tumble dryer, and must have been on the go for about 20 years (there's still some of the original liqueur in the bottle, and I keep it because it looks particularly venerable and ornamental). It came as a bit of a surprise when I tried it more recently to realise that I really didn't know what it was meant to taste like. My current bottle has only been on the go for a couple of years.
The moral of that story is not to let things hang around to long but to drink them (always in moderation). I use drambuie in chranachan (though that to is sadly moderated) and soak the Christmas pudding in it, and just occasionally drink it too.
The legend of Drambuie is that it was a recipe passed on by Bonny Prince Charlie to a family that aided his escape. Wikipedia, some historians, (and boring common sense) suggest that this is probably a made up marketing ploy - which doesn't matter in the least; a good story is a glorious thing in its own right, true or not.
It also means that the obvious choice of reading material is anything that harks back to the 1745 uprising. The Master of Ballantrae hits the spot for me on this, the master himself has an over the top air that suits a Drambuie, and vice versa. 'Kidnapped' has an altogether different atmosphere. 'Waverley' might fit the bill as well though. whichever Jacobite themed romance (suggestions are welcome) you can think of though, a small glass of Drambuie (even better if its one of those beautiful jacobin glasses - or a Victorian knock off. And if only I owned either...) could only add to the atmosphere,