Weeks maybe, but I don't ever think one has lasted for months. Helena by My Chemical Romance has been my jam for about two weeks.

Ear worms can only be evicted by another equally annoying song, in my experience,

I've had weeks long earworms with no rhyme or reason. I agree with Victoria below the best way to combat one is to listen to something else a lot. In the past have had to replace one earworm with another.

Judas Priest, 'Grinder'. Saw the video a few weeks ago and it's stuck in my brain. That and 'Trashed' by Black Sabbath. Damned YouTube....?

We had Joy we had Fun We had Seasons in the Sun. But the Hills that we Climbed were Just Seasons Out of Time.

My solution for that is to listen to the song beginning to end. you need to teach your mind the ending of the song so it does not perpetually loop.

Depriving yourself of the song only makes it worse.

Legend of a Mind - the Moody Blues - for 2 days now

And so often a completely random 70's song that I have no attachment to....or even actively hate.

Here ya go!

People at my work sing. That gets stuck in my brain for day. I have to walk away. It's horrible singing! Customers end up hearing it too! My ears! Most songs don't replay in my head with my music.

Not for months on end but have had songs in my head for hours. Can't imagine what it is like to have it day after day.