According to this website I found: http://listverse.com/2010/06/14/top-10-misinterpreted-song-meanings/
Phil Collins's "In the Air Tonight" which is used and became hugely popular due to the Cadbury's Gorilla spot is actually a bitter song about divorce. Yes it makes you feel good but not really the right message for a glass and a half productions surely! It's not a glass and a half of joy you are hearing, it's actually a glass and a half of bitter gall.
Here's what Listverse says:
"Misconception: Witnessed a preventable death
The dark, accusatory lyrics of this song lent themselves to one of the most well known incorrect meanings. The story says that Phil Collins saw someone drowning once from far away, and that a third person, who was close enough to help, either ignored or refused to help the drowning person. Appalled by this, Collins penned this tune as an anonymous condemnation of the person’s cowardice and/or apathy. Some versions of the story have Collins finding this person at one of his shows and even singing it directly to them. Of course Collins says that story is incorrect, and the lyrics actually arose from the bitterness and anger he felt while going through his divorce."
Here's a video of Collins performing the song - yeh Listverse - looks like you might be right!