I need to show this guy what im made of! suggestions?

ok, ive been dating this guy for 5 years and we broke up about 1 month ago. This is not the first time he has left me, he has left me for another girl twice before, but me loving him sooo much was dumb enough to keep giving him chnaces. Well this time he cheated on me and then left me for a different girl. Im sooo ready to stop being such a weak doormat or the back up girl. however, after how many tears he has made me cry. My whole family and mainly myself is waiting for the day he knocks on my doorstep and i can say skrew you dude and he is the one crying. what can i do to get this peace of mind. how do i show him im not waiting on him or putting up with this anymore?