4 YEARS SEPERATED AND I WANT HIM BACK ?

I HAVE BEEN SEPERATED FOR 4YRS FROM HIM AND WE HAVE REMAINED OVER TIME VERY CLOSE AND HE HAS FINALLY DEDICED TO MOVE ON .... AND I FEEL LIKE IT IS COMSUMING ME... I HAVE MOVED ON AND IN ALL THIS TIME WE NEVER GOT DIVOCED UNTILL 3 MONTHS AGO .... AND TELLING MYSELF BEFORE I WENT IN IF SOMTHING IS WRONG DONT GO TROUGH WITH IT.. AND NOW I AM HERE WITH BOYFRIEND AND HE IS DATING AND I HAVE LOST 20LBS IN 3 WEEKS CAUSE I FEEL AS THOUGH I WANT HIM BACK?!?!?!