Now I'm so dead inside

Ok so my last relationship was with a guy and it ended after 5 years... it really sucked having to break up after going thru so much together but I knew I wanted to move on and this time find the right GIRL for me! (Ive always been bisexual) Well, I ended up falling for my best guy friend... and I must have hit my damn head hard!! There was something about him mixed with the pain of losing my ex that just made me get together with him and go steady. Now, after a significant amount of time dating this guy, I've come to find he has been lying and probably cheating almost this entire time!! I f@$*ing knew it!! I knew I shouldn't have gotten with him so quickly, I knew I should have kept looking for my perfect girl, I knew I should have listened to my gut. And shall i top it off? My grandpa raised me and he just died yesterday. My boyfriend dropped me off at my grandma's, lied to me saying he was going to see his grandma in the hospital and he promised to pick me up later, now today? He hasn't picked me up or even picked up the phone, I found out he took this blonde girl to a music festival in another state for the weekend... I'm such an idiot, I hate myself!!!!! I'm so devastated!!!! This relationship has literally destroyed me more than I knew was possible.... How can I ever put myself back together after this?!!? How will I ever be able to find someone who really cares about me and loves me?? He's made me lose myself almost completely....