Who are we really?

Hi! Coming to understand that circumstances are neutral and our thoughts are choices has been so freeing! Given that any thought is a choice we can program deliberately, how do we know who we really are? Are we our preferences that lead us to the thoughts we choose? Are we the consciousness that makes the decision of what we choose? Is this even a question that needs answering? I’m loving the work; perhaps just overthinking it a bit. Any light you can shine on this topic is appreciated.