Why is he getting mad now?

i hav been dating this guy for 4 years now n thru that tym this guy has given me endless heartaches with his ex,i find proove of thea comunication n he twists it around to make me look lyk the bad guy,recently he left his facebk on n i desided to check n i found he's been emailing the ex telling her how she loves her to death n wuld do anything 4 her n i jst snapped n desided i hav kept my cool for 4 years n now its tim to put an end to it bcoz he used to do somthing to hurt me n runs to chart with the ex of how miserable i was n now i jst told myself no mo hurting n so i said i wunt allowe the circle 2 continue so i startd going out n i stopped being the cheap house help he had cleaning up after him n now that i am having fun with my gals he is getting pissed off,he lyks seeing me miserable n sad n i desided this time i wunt giv him that n now he is outregiours!why?he gave me continuors heartache for 4 years!