"As a psychiatrist, I’ve seen how intense sexual attraction is notorious for obliterating common sense and intuition in the most sensible people.
Why? Lust is an altered state of consciousness programmed by the primal urge to procreate. Studies suggest that the brain in this phase is much like a brain on drugs. MRI scans illustrate that the same area lights up when an addict gets a fix of cocaine as when a person is experiencing the intense lust of physical attraction. Also in the early stage of a relationship, when the sex hormones are raging, lust is fueled by idealization and projection–you see what you hope someone will be or need them to be–rather than seeing the real person, flaws and all."
Via PAT NOVAK