Was my ex boyfriend cheating on me?! How do I get revenge? 10 points!?

Okay, so my boyfriend just broke up with me last Friday. Stating he had to get his prioraties straight but that he does see a future for us again and still loves me. His bestfriend also told me he said the same thing to him so I don't think it was just lip service. But he went out last night at a party my friend was at she told me he was flirting with every girl saying he could do whatever he wants now that he's single. But he also told that same friend that he likes another girl and said 'now thats who I want next ;)" Two days after. What happened to being in love with me? And that it was just a break not a break up crap? Anyways my point is last wednesday (we were still toghether) he asked the girl he says he now likes out. There was other people but he called her and asked himself. He never once let me know he could do anything or tried to call ME his girlfriend. Infact he told me he was grounded that night. Again I found out from another friend. Also he told me Friday that he was grounded all this week as well. Funny how he's been going out every night. Oh, and he lost his phone so we were talking on facebook ( i know pathatic) haha but he did find a way to call the same girl he likes now. Not once me. He even wrote on her wall "hey, call me gotta talk to you about something!" That was also were still toghether. I have a feeling he was telling her his feelings for her then. He did this same thing in the past to an ex girlfriend calling another girl telling her that he was in love with her but telling her to keep it a secret while he was still dating the other girl. What should I do? Is that cheating? And he also still thinks I'm sitting at home waiting for him cause I kinda agreed to that :/ Im done being nice I really wanna get him back and do something to make him realize I can be with other guys too. So how should I handle that too? Thanks and God bless<333