Hi cj,
I have looked at nhs counselling but there is an 18 month wait here at the moment.
Stress, anxiety, and dramatic events can all cause these experiences in my opinion. "Mental exhaustion" can lead to fatigue which defintely can make us feel like we are not ourselves. I think this is quite common with many of us here in this community.
I believet he best way to deal with it is to confront the source of your anxiety. Do you have access to counseling? For me, talking it over with a professional, shed light on why I was feeling the way I was feeling and gave me the tools to confront it. Keep us posted.