I'm sorry you are going through so much, but I think there is a light at the end of the tunnel. I have no doubt in my mind that you are quite capable of taking this bull by the horns, as evidenced by your past in trying to handle this problem.
First of all, I HIGHLY recommend that you make and appointment to see a skilled clinical psychologist for weekly or bi-weekly therapy, in conjunction with med-therapy (if you want to continue meds for depression). Anti-depressants can seldom do the trick alone, and psychiatrists are not adequate for psychotherapy. ECT is only useful for an otherwise unsolvable crisis, and it doesn't solve long-term problems (if it solves anything at all).
I do not know why you would ever be given the option of taking drugs for bipolar disorder, considering that they were not sure if you had bipolar at all, and have not given you that diagnosis yet. I'm glad you discontinued those meds.
I also looked up Parnate on RX List.com: </font><blockquote><div id="quote"><font class="small">Quote:</font>
PARNATE should not be administered to any patient with a confirmed or suspected cerebrovascular defect or to any patient with cardiovascular disease, hypertension, or history of headache.
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RX List Contraindications for Parnate
Personally, if it were me I wouldn't continue with the Parnate. I see it as having no benefit in your case at all if you continue it, and quite possibly harmful to you. I had to look up rTMS/TMS (Transcranial Magnetic Stimulation), and what I found was that there is no evidence that it works at all and is still being studied by the FDA for it's efficacy in treatment of depression.
If you decide to discontinue it, I would make sure that you follow the instructions for discontinuing the drug.
In my personal experience, quitting working only makes depression worse, and people become more isolated and shut-in than they otherwise would have. Believe me, I know.

There isn't anyone I know who has depression who has been helped by quitting work altogether. I would discuss this with the clinical psychologist (that you will hopefully make an appointment with)

There are alternatives to that step, including a reduction in hours/change of job, amongst others.
I would also encourage you to make an appointment with a different psychiatrist for a second opinion, one that is not connected to your current one in any way, and that doesn't have your current psychiatrists records. A clean, unbiased second opinion is in order here. Sometimes even a good psychiatrist can be biased in his clinical judgment and miss things.
If you have unresolved AFIB, then you really need to be evaluated by a cardiologist for your health. The reasons behind the AFIB you have developed need to be determined and ruled in or out as the cause of your extreme tiredness. All medications and health issues need to be evaluated for the necessity of continuing them.
A family physician is great for a lot of things, but you really need to see a specialist in cardiology to evaluate your heart condition so that it doesn't get worse. The hypothyroidism could even be the cause of your depression, and if you aren't seeing an endocrinologist for the hypothyroidism, you really need to be. There are many causes of hypothyroidism, and many types. Sometimes just by taking something like Synthroid or some other thyroid replacing hormone, you can stop the depression in it's tracks. Other times, there are causes for the hypothyroidism that can be addressed and you won't even need medication.
Likewise, you need to address any underlying issues you may or may not have, such as obesity for instance. If a person has obesity, they can cause a host of serious health problems, such as major cardiac issues. When women go through "the change" and their hormonal levels drop, depression is likely to occur (amongst other medical issues), and that too, must be addressed. Daily migraine medicines can cause all sorts of side effects...
Make an appointment with a clinical psychologist for weekly therapy (at least), and very important---make an appointment with a cardiologist ASAP. I would also see a different psychiatrist altogether, and tell him about the thyroid issues. Maybe he can resolve that without having you see a endocrinologist-- however, with your complicated health issues, I would encourage you to see one anyway.
It's very difficult everything you are dealing with, and no doubt it can be very overwhelming! Good luck, and please let me know how it all turns out for you. You can PM me to let me know if you don't want to address it on here.