I'm rather depressed today

I'm rether depressed today. I have given my interest to people who need love, but as soon they got their boy- or girlfriend, they abandoned me and didn't pay attention to me. And I give my love and attention to a girl who I love, but their responses are so insincere and they pretend not to recognize my interest. It is too harsh treatment. Even there's no one who can love me and pay attention to me. It's the most harsh thing in recent in living.