We broke up but i still need help?

on saturday my gf and i were hanging out with 11 of my other friends. i knew she wanted to be my friend but she thought i was too sweet of a guy so she didn't really want to. i decided to tell my friends i might break up with her and made up a boogus reason why. they were talking to her about it and i was talking to them about it. on the way to my house my friend says bluntly "so you guys breaking up yet"? and then she said after a 5 second pause. yeah i think we should just be friends. and i said okay. and then when we went to my house the guy who asked that question was already putting his arm around her and sitting next to her. and when we dropped her off they both hugged and went in. 3 days later she told me she says shes sorry for moving so quickly and how it must hurt me. and now.....idk what to do. what can i do? cause i still have to hang out with them and their going to wait a week until they date. i feel like i souldn't care anymore but i still like her and have to talk to her everyday....... please....help?