In the middle of his life
He left his wife
And ran off to be bad
Boy, it was sad
But he bought a new car
Found a new bar
And went under another name
Created a whole new game
And the days went by like paper in the wind
Everything changed, then changed again
It's hard to find a friend
It's hard to find a friend
Meanwhile then
His wife's boyfriend moved in and
Took over the house
Everybody was quiet as a mouse
And it changed their lives
Changed their plans
Slowly they grew apart
Boy, it woulda broke your heart
And the days went by like paper in the wind
Everything changed, then changed again
It's hard to find a friend
This is just a complete guess, but it sounds to me like this is the narrator's father. After his father left, during a midlife crisis, of course, his mother moved on, her boyfriend moved in and it made the narrator's life miserable. Probably during his early teen years (assuming, because of the "quiet as a mouse part - teen's like to play their music loud). Then his father never found the happiness he was looking for, but he couldn't undo what he did so he lived out his days alone.