Lyric discussion by Judoapples 

I think that this song is about a man suspected of cheating by his girlfriend. The two are in a fight over a suspicious telephone call. When the girlfriend asks 'who do you think that is there?", the guy responds reasonably by saying he only calls people back when he knows who they are and that he doesn't see them, in other words, he's not seeing another person. The line 'I always fall in these fights' suggests that he has these confrontations regularly, however, despite it all he still remains devoted to his girl.

Also, I think that the line 'I know now not to swear' is 'I know now not to stare', which coincides nicely with my idea.

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