This expression is first found in Chaucer’s Merchant’s Tale, circa 1405:

For loue is blynd alday and may nat see.

It didn’t at that stage become a commonly used phrase and isn’t seen again in print until Shakespeare took it up. It became quite a favourite line of his and appears in several of his plays, including Two Gentlemen of Verona, Henry V and this example from The Merchant Of Venice, 1596:

JESSICA: Here, catch this casket; it is worth the pains.
I am glad ’tis night, you do not look on me,
For I am much ashamed of my exchange:
But love is blind and lovers cannot see
The pretty follies that themselves commit;
For if they could, Cupid himself would blush
To see me thus transformed to a boy.