Chris -
I know you are struggling with so much, right now.
And, now that your brain is no longer charged with the high-level adrenalin it needed to initiate your life-altering decision--confront your partner--and watch her physically move from your life (seems she left you "emotionally" long ago)--you are faced with the chemical let-down--as all that adrenalin just drains away. So....just right there....would be enough to precipitate the doubling of depression that you've been experiencing over the last month(s?).
And....in addition to the above chemical reaction, you've just been hit with the sudden reality of a new life...a life apart from your ex...with all its emotional and physical implications:
--the loneliness and isolation..the "void".
--the ruminating on "when" and "why" (which is, unfortunately, inevitable)
--the sudden draining of all your anger...followed by continuing "jolts" of emotion....as your heart alternates between anger---and hurt.
--concern for your future...will you find someone to love and be loved by, again? (you
will!)
--your own physical health...recovery from your operation...and the constant jarring reminders that you need physical assistance until you are well, again.
(Check with your state government--here in New York, after an operation such as yours, you'd be entitled to free help for a certain amount of hours per week, where an aide can shop, drive you to appts, tidy up, even help you shower!)
--the 24/7 shifts you must take to guard against the insidiousness of addiction. (And you've done this with such strength and determination!!)
--all the ordinary paperwork, medical claims, etc, etc, which may be swimming around in your brain, causing you stress.
This list could go on...because there is so much pain you seem to have been "assigned"--all of it simultaneously. But my only point in drawing up such a wretched list (uh oh.....I'm just thinking....ya gotta
promise me you are not going to reread this list one more time, halfway down your plunge fron the roof of the Empire State Building!?!?! )LOLOL!!!

Anyway...my only point is to say you have every RIGHT to feel so depressed. And while that's no help at all....I did want you to realize that, 'though your depression has bcome a chemical one, it is definitely also a
"reactive" depression, as they call it--it has started based on "real" life events. It is not "endogenous"--seemingly out of nowhere.
My own personal belief about depression is that some of us have a predisposition to chemical depression--our brain chemistry is hit and jarred by a catastrophic change, loss, etc. It starts out as very understandable "grief" or "misery" or "dreariness"--but, then, for whatever chemical reasons our brain circuitry goes askew--and set off a chain of reactions that alter our brain's ability to produce and pass along norepinephrine. Our receptors are incapacitated.
Now this is just one theory of depression....but it's the one I believe...primarily, because all three of my worst clinical depressions were "textbook" cases!!! Therefore, I am certain that the healing antidepressants you are taking are building up in your body.....and "recircuiting" the chemicals you need. (I would really like to know, when you feel up to it, what your psychiatrist suggested re. antidepressants. There are so many new drugs that I do not know about---I really need to reeducate myself. )
Why am I going into all this stuff that you probably already know? Just to reassure you that you not alone. You do not exist in a void. Even though you may fear that you won't come back to the world as you knew it (and this is where I had such panic and anxiety), you WILL.
Any of us who has experienced this demon depression, understands completely that fear, horror, etc. you are going through. As I've said in another post...it is not a feeling that can be described. It has little resemblance to grief or sorrow. (My grief at losing my parents was real, honest, long-term misery--it was NOT "depression.")There just are no words for the sheer magnitude...the overwhelming terror of it. And...as you know from "being there" yourself...this is truly not an effort on my part to be melodramatic..or to "overkill" the word "depression." It is simply indescribable. (Although, Andrew Solomon, in that book you're now reading, perhaps comes closest to verbalizing it.)
I just want you to know that you can ask me--or share with me---describe to me--absolutely ANYTHING about your fears, your questions, etc. If there is anything that will make this period more bearable-- I want to try to help you. When I was at my worst, I could not really talk...write...etc, very much. My senses were "zero"--like I was dead. But...if you DO feel up to it....and it helps...I am here for you. (For your depression, your addiction....and any aching that is in your heart.)
I can promise you that you WILL, soon, see a chink of light peek through that door..and it will get stronger and stronger. You must now try to have faith in your new doctor's plan--and the new medications you've been prescribed. You must give it time (unbearable, I know!)....and just hang onto the hand of a friend during this wait. And...of course...I know you know that you have so many loving "hands" right here for you!!
thinking of you with love and concern, Lynn xxx