I do believe in music being a fun, casual & light-hearted part of my personality So its not odd at all that spontaneously a song might pop-out for no particular reason at all.
So, yeah she is used to that.
Spontaneous songs pop in my head and out of my mouth all the time with no warning. I feel ya. I used to think I was picking up radio signals in my dental work, but now all that metal is gone and it still happens. It’s rarely a song I like, but almost always a song I know every word and I can’t shake it until I go through the entirety of the song including the bridges, choruses and solos.