How to get over this......?

well there was this girl i liked and she basically dumped me online and it was the worst pain i ever felt I've heard of people talking about getting dumped and they said it fells like there heart got ripped out and i really didn't believe them until now and this just happened last night i really just want to move on but I'm still gonna see her at church & everything i think that's gonna be the worst part how do i deal with it? pls help this has like tore me up so bad and i have no idea what to do