Is he cheating?????? ?

going on 2 years now and we been through alot of crap mostely cause of me and my trust issues and how i ume well cause im dum and dont think before i talk .. mainly cause of past realtionships .. anyways i went through his phone calls online and didt find anything really bad [ i looked at the mins ] and i saw oo1 for 45 so i called the girl and found out they were just friends he got mad ofcoarse cause he said thats not trust than the next day i saw 56 texts so i said wtf is this and he said chill its all with me and my cussin joken around .. [ cause he just got unlimited texting ] anywayss now he changed his pword so i cant see it and im wondering why???? what do all you people think???? he said because its called privacy and trust and he said i dont go through your emails. he lets me go through his phone and he didt get that mad when i saw it online but when i called him he did maybe hes sick of me spying???? what do you think?? should i be worried???? give me advice on what should i do ... i dont wanna leave him ...hes a sweet guy i just screwed up alot .. cause im scared. i always been through really bad realtionships my ex got my bestfriend preggers and married some other girl and was abusive and for the first time i found someone good and that scares me like when is he gonna change??? helppp pleaseee