What is your advice regarding divorcing while having major treatment resistant depression? could it help the depression?

Uncertain: Divorce can have both effects on depression. It really depends on the marriage and the depression. I strongly recommend talking with a psychotherapist at length before making the decision to divorce and perhaps consider couples counseling in addition to individual therapy for yourself. Major depression and marital dissatisfaction are separate entities that can/do contribute to each other.

Need more info.: It's hard to make a rational decision about anything when you are severely depressed. Is the marriage breaking up because you are depressed? Are you depressed because of the breakup? What have you done for the depression? Depression might be "treatment resistant" because drugs are not the answer, psychotherapy is. And many other questions.

Depends: Divorce is a major decision of life and has tremendous psychic impact even for a non-depressed person. Depression can cloud your judgment at times and itself is enough to strain relationships. On the other hand if your spouse is the trigger and cause for your depression it might help. Talk to your therapist/psychiatrist as the option of interpersonal and couples therapy should be explored.