Dealing With "Semi-Depression" (Of The Romantic Sort)

I don't know why it is, but recently, I've been hit with a very heavy dose of loneliness.  Well, actually, I do know why this is happening; it's those old romantic feelings again.  

If you're a good friend of mine, then you've probably heard me say that I've found the love of my life, so to speak.  At a time when I was in dire need of a good friend, this person helped to bring light back into my life.  It is an unfortunate reality that my "intended" doesn't seem to feel the same way about me that I do her.  I sometimes find this fact to be very hard to deal with, and quite saddening.  I've tried to move on to other women, but I can't do it.  Frankly, I keep asking myself the same question: how can I give my heart to someone other than my intended, when my intended already has my heart? The apparent answer to this question is that this is impossible.  

I usually have many ways to deal with a bout of the above feeling.  When loneliness of this sort hits me, I'll listen to music, talk with friends, write, or find another way to take my mind off things.  This notwithstanding, I find that my attempts to "roll with it" have not been working as of late.  I've been shaking my head a lot, and wondering why the situation is the way it is.  Perhaps part of the problem lies in miscommunication.  

You see, the woman that I'm referring to is aware of my feelings for her; at least, I think she is.  Nevertheless, I'm quite uncertain whether she knows how strong, and deeply rooted, my love for her is.  Simply put, to me she is the stuff of legends and miracles.  This woman means everything to me, and always will....I'm just not sure that I've ever effectively communicated that to her.  And yes, it is quite hard for me to even write about this; it is difficult for me to express my feelings.  Somehow, someway, I've got to find a way to do so....before I go completely bonkers.  Any suggestions, friends?