Love is "blind" when one has no "mind".
Never separate your mind from your heart when making relationship decisions.
The purpose of the mind is to protect the heart.
The love is blind mentality is usually coming from someone who refuses to see the truth or chooses to ignore "red flags". The more they want someone the more crap they'll put up with.
Not wanting to see and being unable to see are two different things. Each of us (chooses) our friends, lovers, and spouse.