beautiful yet hurful

i was just wondering,do love such as fashion also changes as time passes by?
i have a best friend who once told me, the real love will never change. as a girl, i would love to believe and feel that.
but as a person, i do not see any relevant in that. i've never been broken-hearted, never been rejected and said no to, because, most of the time, when the relationship started to have some poison, i'll back away, and move on with another person. (yes, i know, i'm a chicken) which is kind of hard for me to believe an eternity love that will never change.
even the Shakespeare's Sonnet 18 suggested that love will fade. i know i'm not very pious but i think the only eternity love is for GOD. you might be laughing hearing that from me. but that's what i think.
i had the best moments in my life with my loved ones, the worst ones too are with them, but i never regretted for ever being with them. experience makes one wiser.
i used to wonder, why is there even love in the world when your love is not returned?why do paper money worth more than the coins, considering the coin's worth in a way to make it from the minerals are much more expensive? why do people take the love the had for granted and just waste it on other things?
love is such a beautiful thing if u're in it, a real unwanted thing if you're outta it, and is something that u need if you're lonely.
i used to love someone, so hard, that there's no way of me to forget him, that i spend most of my moments creating illusions that i might be in an accident and just hit my head on the pavement, and forget bout him. that's how i feel.that's how i want things to be.but it's not gonna happen.