I want to die (my heart is broken)?

My ex and I have being talkin for over a month. He gave me a pword to his MySpace I read the messages they were all from his exs he even told each and everyone of them that he wanted to get back with them. We got back together for about a week now. There was this message he send recently saying to the girl to call him asap. I want to break up with him so he can keep doing his flirty thang so it wont hurt me no more. WHY WOULD YOU SAY YOU WANT TO GET BACK TOGETHER WITH ME IF YOU WERE ASKING ALL THOSE OTHER GIRLS OUT?! right? plz help!!