As you probably know, DBT is common for Borderline.
My personal favorite is CBT.
When I was in inpatient treatment at the Eating Recovery Center for Anorexia - binge eating/purging type, their main type of therapy was ACT. They also treated all types of eating disorders, and different inpatient facilities have different "main" therapies.

In my unprofessional opinion, I don't think there really is a best therapy for bulimia.
I have a friend with Bulimia C-PTSD and BPD, and her eating disorder flares up around trauma anniversaries, because she has never done the intense (and painful, I know) trauma work it would take to help her with her ED behaviors.

Eating Disorders are SO SO incredibly diverse - despite what the DSM says - and everyone has different reasons for why they start and continue with those behaviors.

So for you, the type of therapy that would be best for you is the type of therapy that treats the underlying reason for your ED.
I know that's probably not the straight forward answer you want to hear, but I hope that helps some.

Don't get discouraged, my friend, on this long road.
Eating disorders are common, yet so misunderstood, and it is so easy to get discouraged at the pace of your recovery, but I am here to tell you that recovery is possible. You have to want it though.

Keep fighting, my dear.
There is hope.