Without pushing your religion on me. someone give me advice?

Okay. i was raised as a catholic...not a strict catholic, but we went to catholic church and i did ccd classes and did the first communion thing. anyway. my dad passed away when i was 10. he was the one that pushed me to do those things. I have not been to church since he was alive. i have no desire to go. i did believe in god for a long time. then one of my really good friends passed away for no reason and he did not deserve to die and did not live out his life and blah blah blah. since then i have questioned everyithing so much more. I just dont know how i can belive there is a god if he let my dad and friend leave me. and i dont want to hear everything happens for a reason. someone just explain to me why i should believe that there is a god.