I really like this girl that I meant over the internet but she has a boyfriend.?

I know I'm stupid for falling in love with someone I meet over the internet. I know. But I really fallin in love with her. We dated before not irl but on the internet, so I guess you can say we're "Net Dating" But the thing is that she talks about our future, and everything. Then the next thing you know she told me she has a boy friend now. That she's the one for her, and everything. And that really hurt me. You get where I'm coming from? Should I just break up with her? And No we never meet before, She lives in New York and I live in Washington. We talk on the phone once in a while though. Can anyone help me? Please...