What I learned with PCS and depression/anxiety is that it is a chicken and egg situation. They both make each other worse, and they both have overlapping symptom sets. You probably will never figure out exactly which thing is causing what. Your neurobiology affects your thoughts -- but your thoughts also affect your neurobiology.

The good news is that if you work on getting your brain into optimal working condition, it will help both the PCS and the depression/anxiety. What heals one, in general, also heals the other.

There are a few PCS-specific things like vision therapy that can help PCS alone, but even muscle tension and back or neck pain can be related to either PCS or depression/anxiety. In my situation, it made sense to stop focusing so much on where the issue originated and just working on getting my brain and body into optimal working condition. Then everything got back on the right track.