fail.
I completely disagree with the previous quote. The only time unrequited love equals self-inflicted pain is when it is secret, which is cowardly.
Unrequited love makes the holder angry, frustrated and sad, eroding self-esteem, and the object guilty, angry and, eventually, callous.
Falling in love (or lust) with someone makes you believe that you have a claim over them, if nothing more than basic kindness and respect for your feelings. When the object does not reciprocate the love/lust, this claim becomes an onerous and tiresome burden. You lose respect for the holder, and the obligation to treat their feelings with courtesy becomes meaningless.
Honestly, I don’t understand how enough people’s lust and loves match up to perpetuate the human race. I guess that was the benefit of arranged marriages.