To let go or to hold on?

I have a boyfriend that makes me feel truly loved and I can honestly say that he deserves 100% of my trust BUT the thing is... he's good looking and a lot of girls are all over him. I don't really mind but there's this one girl who likes him and hangs out with him a lot. Oftentimes it's just them two because they're both irregular students and the girl kinda made her schedule so that she'd be classmates with my boyfriend. I'm from a different campus and I don't want to hinder my boyfriend on any sort of growth and I don't want to be the type of girlfriend who's controlling so I just leave him be on the matter BUT I can't help but feel restless and troubled about it. I trust my boyfriend but I don't trust the girl. The girl knows my boyfriend is seeing someone but we're both in a "secret relationship" wherein the public nor our families know we're both together. You see, there are factors in our lives that hinder us from making it public so we just let everyone know we're not available to entertain others. And the thing about this set up is that the girl may think my boyfriend isn't serious with me since we have to make it extremely private? And at the same time, all this obstacle between us is kinda making me lose hope. I want to flaunt to the world that he's my boy and that I'm his girl but due to some annoying factors, we just can't and it's sad. One thing's for sure is that we both truly love each other to the point wherein he traveled to the other side of the world just to be with me.