What is the song too close for comfort by mcfly about?

"Too Close for Comfort" by McFly is said to be about McFly lead vocalist Danny Jones feeling insecure in his relationship with his then-girlfriend. In order to keep that connection, he sings about making it work by changing to keep up. The line in the chorus, So you know that every little word has my heart in it / I hope the song is still in tune 'cause my feelings still aren't speaks the most to this concept in the lyrics.