Do you see how this is not working? After 2 years, you are still overly attached to your T, maybe more than before.
We have discussed IFS before and I mentioned that the literature suggests that it does not work well with those with borderline traits because they fight moving to the Self, because all their parts want to get their needs met.

You fight moving to the Self all the time.

The reason you think this is working more is because you are getting what you "want" from your T. It is not changing your pattern.

Usually DBT is done with a DBT therapist and a DBT group. A DBT therapist is trained in the methods. The group is used for skills development.