i think there are two parts here, and i'll speak to them both. First, if a person cares for, is infatuated with, or feels that they are in love with someone who does not reciprocate those feelings, that person is in a place of self loathing. it is a process of believing that one is not worthy of recieving love, and so seeking love from those who do not want to give it. It is an issue of attachment--hoping for something that will never come, and using that as a mechanism of suffering rather than letting go of the illusion of the need for that person, and instead seeking out a vibrant, creative, healthy, loving relationship with someone who will recipricate.
This understanding came from my husband's experience--as he often found himself in this situation. After deep contemplation, he realized that it was a self-fulfilling prophecy of the idea or belief that he was unworthy of love or that love was difficult to achieve. he had many life-lessons in early childhood that taught him that real love was meant to be hard or unrequited, that having your needs met was selfish--and so he would get himself in these situations because he thought that was normal. once he realized that this was an active form of self-loathing, he began to engage the people and his potential love relationships differently.
i've been on the other side of this fence, being the one who was unable to return someone's affection for any number of reasons. most of my reasons were deeply personal--such as the idea that i wasn't ready for a relationship--and some of them were more vague--such as i simply wasn't attracted to the person.
for me, it was a difficult and often uncomfortable situation. Often, these people would strive to be my friend in the hopes that i would at some point 'come around' to their position and return their affections. Unfortunately, the relationship or friendship was always tainted with this weird longing from the other side--a sort of neediness that made me uncomfortable, mostly because i knew that i couldn't provide what the person wanted or needed. THis of course often upset me, because i do not like for people to suffer. But i also knew that it would be inappropriate to give in, simply to avoid their suffering--because not only would they not avoid the suffering, but i also would suffer by doing something that was n ot true to myself and my feelings.
So, i would often befriend them, but at arms length. If they could, in time, work through their feelings and engage me at the friendship level, then i would increase the amount of time i spent with them. In the beginning, it was always rather distant, just to make firm the boundaries that i needed to set--physically and emotionally.
if they couldn't work through their feelings, and if on every occassion of our relating they brought up the issue of going out, tried to be physical, or tried various methods of emotional manipulation to strive to convince me of their worthiness (which is really convincing themselves of their worthiness), then i would eventually get fed up and discontinue contact completely. Often, i would have to be very firm with people--particularly when they would call me 3 and 4 times a nite, and then ***** me out when i wouldn't call them back within the time frame that they wanted (the same nite). I had to be firm about this more than once.
So, that's basicly what i did.