How do I get over this and be happy?

ok I just joined this site.. so I hope im doing this right and I hope someone out here can give me advice.. ok I have been with a guy for almost 5 years and now we have been broken up for almost 2 years now. and we were engaged and we broke up the same month we were suppose to be married (very hard) needless to say I broke it off cause I was seeing the flags pop up that were making me think he just didnt want to be together now more, so I broke it off to give him his time and I was thinking he would come back after a couple of days to weeks NOPE never happened and trust me I tried getting him back I guess thats what he really wanted is to break up but I thought for sure he would come back.. so I dated others for rebound and he did his thing and trust me I was thinking about him 24/7 and still do till this day.. I keep praying and hoping we will get back together, now he lives in our state were we grew up because he was in the military but nows he out so hes living in same state as me and its soo hard cause I want to see him but to scared to call him I did once and he informed me is seeing someone else my heart sank.. cause ever since we broke up I was telling him I want him back so he knew that. im just so hurt and im afraid he will marry this girl cause hes the long realtionship kinda guy. I still talk to his sis and im afraid one day I will hear hes getting married.. how do I get over this and be happy. I miss him soo much and want him back he was my first love, im afraid ill never get over him.. and I know they say the amount or time that your with someone it will be half that to get over them.. well I hope thats true cause im almost to that half point well please help