Well, Birchy, I'm not sure that it's fair to say that absolutely in a colloquial sense means 'anything but the absolute' as you state; however, I have to agree that it is more prevalent in the way you describe than perhaps it once was - though I'd hardly use the word epidemic. It is, as you say, used as something of a 'filler', though, and it has many shades of meaning. It's quite useful, you have to admit, and makes a change from OK and 'Ooh, I know' and other time-worn phrases.
Maybe you can blame the successful-ish eponymous Scottish comedy show of the early 90s. They seemed to use the term as a bit of a mick-take of middle-class urban Scots, particularly those from the Kelvinside region of Glasgow, who would say 'ebso-loootely' in a very affected manner. So, perhaps that's the beginning of its current ubiqity. Does that ease your mind?