I quote
"you must know that it is all physical attraction between sets of particles of matter — something that attracts two bodies nearer and nearer all the time and, if they cannot get near enough, produces pain; but where there is real love, it does not rest on physical attachment at all. Such lovers may be a thousand miles away from one another, but their love will be all the same; it does not die, and will never produce any painful reaction."
I unquote

The science behind the emotional pain... this was new to me...

Hard Work Doesn't Kill Anyone... But Why take Chances.