I listen to a song and play it on repeat, learn all the parts to it, memorize the lyrics, jam to it as I do homework... And then one day, I realize I'm tired of it. That's when I'll find a new song and do the same. I listen to it until I get sick of it. However, one day I remember that old song I used to listen to all the time, and I'll start back up on it again. Being sick of it happens for a bit and then I am fine.
It is the same with how my music genre likes differ. 3 months ago I was listening to melodic metalcore. Now I'm listening to alt rock, pop rock, angst filled rock, and cheesy romance rock. It all goes in cycles. Now I'm listening to Boston by Augustana but 3 months ago I'd be listening to Hand of Blood by Bullet for My Valentine. Even the name sounds less metal xD
Hell to the naw! I treat my songs like I treat my women. I ride 'em till they break! Ok, thats not true! But seriously... I don't sweat it! I ain't scaird! I listen to that song till I get bored if I want. I'm crazy like that tho!