Dont want to be taken for a mug again any advice?

recently split with my partner of 6yrs practically overnite he changed his whole life new girlfriend,new job, and even been left a message on facebook sayin she's looking forward2getting pregnant in march he asked for help in quitting cocaine i put so much of my time into it too cos he asked for help, he hasnt seen his children since 19th sep 08 up2 now he hasnt provided anything in anyway for the first three wks of him leaving he had no contact what so ever with us just cut us off,now he's phoning me,been nice in texs and not slaggin me off is he playing me or trying to?