I thought my own two cents appropriate here:

Fromm's Art of Loving.

I'm not generally a fan of post-Freudian psychoanalysts (Jung, Adler, Fromm, Marcuse, et al.) for a number of unrelated reasons, but what Fromm did here is really worthwhile reading, if only to correct the rampant egotism that washes over us every few minutes or so.

In part, reading something like this encourages you to think about what you mean when you claim you 'love' someone.

I found out that I had a lot to live up to, no matter how much I thought I was "doing a good job."

A corrective to emotional arrogance?