Work Romance

I have been having a love affair with my employer two years now.  When we are at our closest it seems he pulls away by not being close and turning elusive, detached, while I am opposite and feeling my closest to him.  So the backing away that happens hurts me just when I am on my biggest “high” in the romance.  Over the two years he has had relations with other women, for which he has lied about and I’ve discovered the lies, nothing concrete enough to know the details exactly, but enough to know he is lying.  When we are around other women he is friendly with he ignores me completely, barely looks at me or talks to me while very fun, charming, flirtatious, and attentive with the other.  So… I’ve been trying to break it off with us.  I’m feeling it isn’t me personally, that he is addicted to sex or the attention, whatever.  Yet I have work related promises I am obligated to, and the office is much more boring and the day is very long when I try to ignore him; the least attention from me he believes we are “together.”  I don’t know what to do except this is hurting me terribly, my heart, my spirit, my body, my mind, my time.  I am suspicious now of every female, and every pretty woman that I happen to see, wherever I am, even in magazines, etc, become example of my inadequacies, while he seems fine and dandy.  I should add he is the best employer I have ever had as far as kindness in the workplace, patience, and sense of humor… and that I am a financially broken single mom of a four year old, and he is super helpful with my single mom life when I have to stay home with her or go to an appointment, so forth.  Quitting seems awful, sometimes, and other times I could walk out of here and never turn back.
Any advice?