PhD, medical leave or dropping out?

First off, I am a first-semester physics PhD student at Minnesota. I had latent anxiety issues for years but never did it get to the point where I could give up on that aspiration because of my mental health. The issues became too severe for me to ignore when the midterm grades were returned to the students in the two mandatory courses I dropped due to the intense amounts of stress they caused. The receipt of said grades happened in early November.

It was disappointing especially since there were massive discrepancies in homework grades vs. midterm grades. Clearly I understood the material just fine, especially since I would try to do the homework on my own, before everyone else starts (and sometimes I could finish homework sets before other people even start) so I know my anxiety is not caused by any intellectual failure. And also I could grade thermodynamics homework just fine; I think it contributed nothing towards my pains since I could still do it just as I used to before the pains cropped up. I made a point to grade these homework as fast as possible since prompt grading would help the students' understanding and learning.

Due to the amount of pain these courses caused, I dropped them, knowing that I would have to retake them at a later point. I spent some time this month trying to understand the pains, where they came from, before I could actually go to therapy, where I asked for an anxiety test and my anxiety was diagnosed as severe. I also thought it would make me feel better once the coursework is over if I somehow improved my PhD GPA over my masters one (that is, if I finished the coursework stage with 3.80+). And I also know that comfort with the material would make me much more comfortable doing research that built on it; as such, poor grades would make me much less comfortable. Now, I understand that there is some disconnect between coursework and research, especially if I somehow did experimental or observational research.

Because of the long lead times to get seen for mental health with university mental health services, I had to wait three weeks to get an appointment and so, in the meantime, I somehow relied on the departmental secretary for support (and almost as if I was using her as a therapist without referring to her as such). All the progress I made with her was that I am now convinced it was not due to some loss of intellectual functions. But my sleep quality deteriorated, my brain fries much more easily now (even though I can still do everything I used to be able to do). And then I got referred in the community for therapy.

However, exercising my waiver options on the first two quantum mechanics courses turned out to be a good move on my part since I'm doing just fine in the third graduate-level QM course, without it causing me nearly as much stress or anxiety as the other courses I dropped. (I technically have three courses left but the other two require no real work on my part and have no substantive physics content, but I have only one course with actual physical content left) So I have made a list of what contributed and what didn't contribute to my anxiety:

What contributed:

• Unhealthy relationship to a prospective research topic
• The discrepancy between homework and midterm grades
• The weight placed by prospective research advisors on graduate-level grades (especially one of the top two choices; the other cares more about a course I have yet to take than any other course)
• The weight I place on my academic performance at large in my self-esteem (perhaps unhealthy, too; I suspect I will have to work on that as well)

What did not contribute:

• Life away from home; it's my first time living away from home - and abroad at that
• Finances
• Language issues
• My TA duties
• My work ethic
• The departmental environment (no PhD program would have a 80% graduation rate without at least some humane treatment of grad students)

By now I would say that, if it was only about intellectual capability, I would be able to carry a PhD to completion since other students at my level graduated with the very degree I am seeking, from that very physics department, in the past. Given the above, should I simply drop out or I should return next September? In both cases, I will return home after the semester is over, continue either medication or therapy.