I don't know if this could be considered an addiction.
Presumably these are medications that are prescribed for you to be taking in the prescribed dosages. But taking them the way you are is certainly is dangerous!
You didn't mention why your therapist isn't giving you your med's as s/he normally does. But it sounds as though it would be wise for you to have someone (your T or someone else) holding your med's for you & giving them to you in the prescribed dosages. I know you wrote you're looking to escape your daily pain.
But taking large amounts of prescription medications isn't the way to do it. Please take care...