Everything said above is good and helpful, and I wanted to add a couple things too.
Your insecurity is a huge problem and something you need to work on, with a T if possible. No one can fix you except you, with professional help. And really, what are you trying to accomplish here? Controlling her? So what if she has all these extracurricular interests? It is who she is. If you don't like that about her, can't accept that without going into insecure mode, well, it is your problem not hers. She clearly lies to you because she feels you won't accept who she really is.
Perhaps, starting today, you stop obsessing so much. It sounds like you may be expressing that obsession/insecurity verbally? I hope not.

Today, start living, one day at a time. What that means is ...no thought of yesterday, no thought of tomorrow, just live in this day. Make it the best day you can.
Be the best boyfriend you know how to be. She is with you, accept her, accept yourself with her.
And while I know talking is great and necessary in a relationship, I think perhaps you are talking too much about this, and your insecurity. To her and to yourself. So stop. Save that for a journal & for a T.
You need to conduct yourself with dignity. I know that is an old fashioned thought these days, to have self control and to govern your impulses. But if you want to be your best self, the one she wants to be with, try.

Best to you ~ one day at a time.