How to deal with an ex?

All right so a few months ago i broke up with my boyfriend because i just wasnt feeling it. We had dated for about a month and a half. He was so upset about the breakup and everything. We ended up talking about a week after the breakup and were starting to i guess become friends. The problem was, people already knew we had broken up and stuff and it was just plainly awkward. So now, a month and a half later of talking im still confused about my feelings. I like other guys, and i figured it out that i probably was just keeping him in my life if something went wrong (unintentionally) so i told him this. And he was looking for a second chance and everything but i just cant do that. So a few days after i tell him this (days with no talking) he says he wants to be friends. I dont believe he can do this, seeing as weve tried this before and it didnt work, so what do i do? On a sidenote: i like one of his friends... and i think it would be weird if i tried to be friends with him and then maybe i started dating his friend... just sayin. So, should i let us try to be friends? Or should i tell him its best for him if we dont? (<--- if so.. HOW?!)