Why are some guys not contented with just one girl?

what is a perfect girl for you? my boyfriend left me, he told me he found someone else. I'm so heartbroken right now. he said he love me. he is my first bf... I did everything for him and he still left me. I can't sleep, I can't eat, I'm always crying and I don't want to go to school. what to do? :( HELP
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+1 y
i feel better now. thanks girls and guys :)
Why are some guys not contented with just one girl?
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