On the same album as 'How do you sleep' there is a completely contrasting song that sounds like a heartfelt apology. 'I'm just a jealous guy' If John really was jealous of Paul and Linda's relationship then this song would make sense. He didn't mean to upset Paul but since he couldn't control his jealousy he couldn't help it.
"My song, melody written in India. The lyrics explain themselves clearly: I was a very jealous, possessive guy. Toward everything. A very insecure male. A guy who wants to put his woman in a little box, lock her up, and just bring her out when he feels like playing with her. She's not allowed to communicate with the outside world – outside of me – because it makes me feel insecure."
If Paul had wanted to make their relationship open, and John didn't then this would make sense. There would be even more people for Paul to love and John didn't want that.

Johns song 'I know (I know)' also contains some references to Paul. One lyric says "Coming down" and Paul's song "Coming up" is what made John wrote music again. Also the line "I love you more than yesterday" When John talks about Paul in a song he tends to reference the song yesterday. There's the line "And I know it's getting better all the time" which is a direct reference to the song getting better. Paul and Johns friendship might have been starting again.

The song 'Best friend' by wings is probably about John as well. It's about someone (a best friend) treating you bad but the subject still thinks about them.

'No words' by wings seems like it's about not being able to tell someone you love them (a recurring theme in Paul's songs) The line "I wish you'd see / It's only me, I love you" is probably referencing the time John pulled down his glasses and said to Paul "It's only me" after an argument.
"You want to turn your head away" is similar to the line "Turn your face to the wall" from the song 'You've got to hide your love away"