In the 1980s, sunglasses were a common fashion for people who wanted to adopt a "tough guy" persona (note all the cop shows from that era -- Simon & Simon, Miami Vice, etc. -- where the lead characters wore shades). So I think this song is about a guy who wears shades as a way of hiding his insecurity after learning that his girlfriend is cheating on him. He's trying to pretend that he's a "tough guy" to hide the fact that his girlfriend's affair is disturbing him.
In the 1980s, sunglasses were a common fashion for people who wanted to adopt a "tough guy" persona (note all the cop shows from that era -- Simon & Simon, Miami Vice, etc. -- where the lead characters wore shades). So I think this song is about a guy who wears shades as a way of hiding his insecurity after learning that his girlfriend is cheating on him. He's trying to pretend that he's a "tough guy" to hide the fact that his girlfriend's affair is disturbing him.
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