Forget Me Not is actually a Greek name for mouse's ear.
The Flowers Petals on the Forget Me Not Flowers resemble mouses ears so that's where the Forget Me Not flowers got the name forget me not.
Of course when you give someone the Forget Me Not flowers you can say I gave you flowers called Forget Me Not and now you must not forget me.
I love those flowers though too and my husband gave me some for our anniversary and he actually said that to me.
I thought it was so funny.