My ( 21M ) girlfriend ( 23F ) said she wants to keep the relationship private

So to begin I ( 21M ) had asked my girlfriend ( 23M ) of 6 months why she hasn’t posted us together any, we’ve done photo shoots together and everything. For reference I’ve posted a small soft launch on my social media a few weeks prior. She told me that she wants to keep the relationship private where only friends and family know about us, and told me I could fully post her myself if I’d like to. I’ve expressed that it doesn’t even have to be a full picture of us, I’d be perfectly okay with just a soft launch photo to allow people that follow her socials to know that she is currently dating someone. I understand wanting to keep it private but it’s hard not to sit here and think she really just wants to keep me a secret from whomever. I am a chronic over thinker and it’s completely destroying my mental. How do I go about talking to her again about it or even just letting it go and forgetting about it? Also I’d like to hear some input on this as well. ( maybe I just need to mature )