Would you be able to trust your bf/gf if they lived 30mins away and went to different schools?

So my Boyfriend is my best friend that i have known since the 5th grade. He is amazing but the thing is that he lives in Deer Valley and i live in Central Phoenix and soon might be Scottsdale. I have always trusted him and he has always trusted me. I mean we have been in love since 5th grade but just recently got together because we were both finally able to. I have never had any reason to doubt him, but now that we are dating it seems different. Like i trust him but im not sure if i do all the way. I don't know what has changed to make it seem so confusing as to why im not sure if i trust him fully.