The meeting of two personalities is like the contact of two chemical substances: if there is any reaction, both are transformed. http://tinybuddha.com/blog/strong-chemistry-doesnt-always-lead-strong-relationship/
I stumbled across this link today: (http://www.syncrat.com/articles/science-of-love). It explains the science of love according to the Helen Fisher model of love which splits our notions of love into three brain functions: lust, romantic love (or attraction), and attachment. She believes love is a drive. This is a quality breakdown of what we’re looking at in terms of hormones and neurotransmitters and their functions.