Hello and welcome!
Anxiety and GERD can certainly be co-morbid...in fact we have a lot of posts from members simialr to you, who ended up having both issues to some degree...one can feed into the other for sure.
Therefore, seeking to treat both of these together is going to give you the best possible recovery and relief from your symptoms.
I believe that therapy could very much help, as well as the self-help that you mention!
Here is the link to our Resources that is full of great material to help get you started. The meditation links, coping skills/relaxation exercises, journaling suggestions and therapy worksheets are all fantastic!
https://www.healingwell.com/community/default.aspx?f=9&m=104206
Keep posting with us if you find it helpful. We understand, care and support if key!
Scaredy Cat