I just got out of a 3year long relationship and i am dating some1 new who i really like am i movin too fast?

my ex and i had a good relationship but it wasnt exactly healthy he cheated on me and finally after along time we ended it...well now i feel like a big pain has been removed i am in a new relationship with some1 who ive liked for a while and things are going good some say im moving too fast but im happy wat do u think and my ex still wants me but i dont wanna hurt him and tell him bout the new guy but at trhe same time i knmno we will neva be 2getha again b/c i cant deasl with it anymore