Hi Crazy Fool - I am always getting myself into this emotional state. I fall for men too easily and always end up feeling hurt and lovelorn. Unrequited love is terrible to go through, but try not to dwell on it and get busy with your social life, do new things go out more and meet new people, and generally have as much fun as you can. Dont tell the person how you feel, not sure why you say you cant be with them, perhaps they are married? It will hurt now and feel like its never ending, but you will find someone to make you go all weak at the knees again.
Take care,
RQ xx