At any rate.
You can picture emotions as nothing more than chemical reactions, but that doesn't make love any less "real" than fear, lust, jealousy, or depression. And chemical reactions are triggered by sensory input (along with memories, which are just archived sensory input). They don't just coalesce spontaneously, which is to say that the result is not arbitrary. It's based on preference, which starts out physically and is perpetuated through mental stimulation.
And by "mental stimulation" I don't just mean philosophical discussion. There are certain things that make you laugh, cry, and cringe. The person who triggers the positive responses the most -- both mental and physical responses -- becomes your preferred mate.
All things considered, sometimes it is good enough to have the luxury of emotional and physical attraction. Millions of people go their whole lives never finding anyone who really rocks their boat.
I don't know if this addresses your concerns -- I've had a couple beers
