Need advise on loosing girlfriend.?

I'm not asking any whys and if ands or buts. I know that my girl of 5 and a half years left me for another guy and I know that she's the happiest she's ever been and that I'll never get her back. All I want to know is how do I get over it? In my heart she was my true love and everything I wanted. She was the one who I wanted to settle down with and have a family even she said that's what she wanted. But how do I cope with it? How do I move on and leave her behind even tho she still has my heart? I want to move on so much but I cant allow myself to it's still seems so unreal to me and in my heart she's still mine. I look at her profile on myspace and see how happy she is with this guy and it just makes its worse. I know I need to stop and that all I'm doing is torturing myself but how? How do I stand on my feet pick up the little bit of pride I have left and look the other way? I really don't know what to do..