The Fool Over The Hill.
You can almost see it: He goes through heartbreak with his latest Ex, then after awhile alone and Every Night in pain, with no one to Take It Away, he decides "I've Had Enough -- No More Lonely Nights! What good is being able to Silly Love Songs without someone to sing them to? Forget my millions, what Girlfriend wouldn't want to have such a talented, Brown-Eyed Handsome Man to spend time with? Let's Have a Party and fun for the rest of our lives!"
The problem with Sir Paul is that with him, there is a Fine Line between infatuation and love, and he can't recognize it when that Temporary Secretary or other quick squeeze is not right for him. Then, when things inevitably go South, it become incredibly more difficult to go From a Lover to a Friend than conversely.
Maybe I'm Amazed that he's even still able (and apparently willing) to go through all this again .... With a Little Luck, perhaps fate will be kinder to him this time.
LOL!