Why did I give up on believing in love?

I'm a successful person who works in a fortune 500 company. But, every time I reach an accomplishment or milestone, there's really no one there to celebrate my accomplishments with me nor do I have a real best friend or a partner. Also, a lot of guys would chase after me but im really tired. Do you guys ever stop believing in love especially because living in America?
Why did I give up on believing in love?
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