Don't blame yourself. This will not help you at all. You need to show some self-compassion. It is something I am practising at the moment, and it is SO difficult.
I sincerely doubt whether your psychiatrist will have a good working knowledge of Kratom - you are far better approaching the American Kratom Association (AKA). They will be absolutely straight with you and are the global experts.
MDMA is very potent. That is a serious drug. Unless you are talking very small amounts, which may be worth trying - but we are talking micro-dosing here. MDMA has been used to "reset" some areas of the brain (keeping it simple), but there is no guarantee of this, and it can be very dangerous in an uncontrolled environment.
This is my area of expertise so I would love to hear what happens with regards to this. Please keep me posted.
If you need any information of Kratom as well, please just ask and I will help. All information sourced (if I do not know for sure myself) is sourced from only trustworthy sources.