why blue?

'Blue-sky thinking':
Creative ideas that are not limited by current thinking or beliefs.

'True blue':
A person who is true blue is loyal and dependable, someone who can be relied on in all circumstances. Someone who is true blue is extremely loyal.

'Once in a blue moon' :
If something happens once in a blue moon, it happens very rarely indeed.

´Out of the blue':
If something happens out of the blue, it happens suddenly and unexpectedly.

'Scream blue murder':
If someone shouts very loudly in anger, or fear, they scream blue murder.

'A bolt from the blue':
A complete surprise, like a bolt of lightning from a clear blue sky.

Taylor Swift
My heart´s been borrowed and yours has been blue... 

Arctic Monkeys,
Suck It and See:
Blue moon girl from once upon a Shangri-La
How I often wonder where you are
You have got that face that just says
"Baby, I was made to break you heart."

Taylor Swift,
Tim McGraw:
Think of my head on your chest
And my old faded blue jeans

Elton John,
Tiny Dancer:
Blue jean baby, L.A. lady, 
seamstress for the band
Pretty eyed, pirate smile,
you'll marry a music man

Arctic Monkeys,
Knee Socks:
When the zeros line up on the 24 hour clock
When you know who's calling even though
the number is blocked
When you walked around your house wearing my sky blue Lacoste
And your knee socks

Fink, Nothing is ever finished:
Baby blue, I really wanna kiss you
But I'm not sure if that's wise

Taylor Swift,
Ocean blue eyes looking in mine
I feel like I might sink and drown and die

Corinne Bailey Rea,
Put Your Records On:
Blue as the sky, sunburnt and lonely
Sipping tea in the bar by the road side

Make You Feel My Love:
I've known it from the moment that we met
No doubt in my mind where you belong
I'd go hungry; I'd go black and blue
And I'd go crawling down the avenue
No, there's nothing that I wouldn't do
To make you feel my love

Young the Giant,
Cough Syrup:
Life's too short to even care at all oh
I'm coming up now coming up now out of the blue oh.
I´ll Be Waiting:
But we had time against us
And miles between us
The heavens cried
I know I left you speechless
But now the sky has cleared and it's blue
And I see my future in you
Adele, Someone Like You:
Hate to turn up out of the blue uninvited but I
Couldn't stay away I couldn't fight it
I had hoped you'd see my face
And that you be reminded that for me it isn't over.