This is long, sorry, please bear with me....
You are not alone in your situation, trust me. Even better, there is HOPE!

I was on anti-depressants
and anti-anxiety meds

for about 5 years (1997-2002). I began these meds when I had a panic and anxiety attack of
massive proportions after two nights of poor sleeping and arguing with my dh. It was not "pretty" and ended with three shots of Haldol to bring me back down off this attack

. The 3-4 years pior to this I was always wondering what the heck was
wrong with ME, as I'd have
little panic/anxiety attacks, long periods of depression I could not kick, crying jags, suicidal ideation,
everything you described.

. I thought I was slowly going nuts


.
During this 8 year period, I went through
four or five therapists, SEARCHING and SEARCHING for what was wrong with
ME! Several seemed "crazier" than I felt (one a bra-burner, another too religious), another just wasn't a good "fit" and TWO were
very good, very experienced. BOTH essentially informed me: "Your
marriage is
making you sick and depressed" and "
You two need to see a marriage counselor before this kills you" one even said: "He seems to need some counseling....

".
Hmmmm....
My marriage could be making me SICK???
SO I convinced dh to go to a marriage counselor. DH said he'd go "
to get ME some help with (MY) issues". "You find one, I'll go...".
DH didn't like the
first marriage counselor, a
woman, because, frankly,
she was a WOMAN and dh believes WOMEN are
less intelligent, stable, ...(fill in the blank)..., than
superior men to begin with,
AND he didn't
like that
she informed
him he needed to work on some of
his "issues"



. In a separate session with me she told me: "I am not sure he
can change, he is a bit of a challenge...I can see..you may have to do all the work". She was kind

. DH refused to go BACK to that therapist. DH's last word: "
Heretic!"
SO, I found another marriage therapist, awesomely recommended,
bulletproof credentials 
! A MAN gender therapist


,
perfect! Because this was a MAN

, my DH thought the MAN

would
easily see I was the one

with all the issues, just a
hysterical, panic-anxiety ridden, wife. DH at one session said to MAN

therapist: "I don't know
why you can't just give her some more pills to snap her out of this..."


" (Never mind, marriage therapists rarely prescribe...)
SO about the fifth exhausting session (speaking with DH is always exhausting for all, as no one gets a chance to speak, except DH), the MAN

therapist announces: "DH, I want to see you, just the two of us, (manly-manly

guys), for a few
visits to discuss some more manly-manly

issues you may want to discuss without the little woman

before we get into this any further" ...

SO, DH goes twice alone into sessions. He
drags me along to sit it out in the waiting room and review magazines...these manly-manly

are to work out the little woman's issues you see... so I
must 
be with him for the visit
After DH's second visit, he and the MAN

therapist come out from behind closed door session. DH rather bolts out of the office, out the door and once outside, lights up a cigarette, puffing long drags, and pacing

The therapist has held me from departing
with DH, by placing his hand on my arm

. The counselor and I are watching DH through the plate glass window, DH is clearly agitated and does not even notice us looking at him, DH even kicks the stones in the parking lot with his shoe!
The counselor sighs, and tells me: "Sandy55, he is something else! I don't know
how on earth you have stood him this long and kept your sanity, you are amazing! My advice to YOU is to get out of this marriage if you can, as he has so much going on, I don't know where to start...". I just stood there, my jaw had dropped. We went to a few more sessions, the therapist would not give DH 'wiggle room' to rationalize his behaviors at all, DH just began refusing to go with me any longer, making excuses.
THAT is the year (2001) I realized, my toxic marriage was going to kill me if I did not get my head around how I was going to NOT let it get to me long enough to allow me RAISE my kids as I chose. Divorce was not an option in my case at ALL.
Appreciate your staying with this long story, to this point, as there is a message for you from me:
If your kids are raised, you can support yourself, you are feeling unhappy, depressed, panic and anxiety, wishing to end your struggles over your 28 year marriage, your DH does not even seem to notice or care that your marriage and his behavior is causing you hurt, then leave it. It is not worth it, and any man who does not notice, or who chooses not to notice is not worth being SICK over as you age.
You simply stuck it out to make your kids' lives more stable. You have done your job and in my opinion it was a noble thing to do: staying for them. It is what I have done, and I do not regret it, although it has been lonely and tough. But it was an honorable thing to do in the long haul.
Be happy. Age healthy. Age well. But do not age due to stress over a marriage that was over long ago - life is only so long

. You can still be friends with dh, but WHY stay married if you have no reason; divorce means freedom for you. Freedom from his constant insensitivity and selfishness. You don't need it, and no longer have to take it!
Hug. Hug. Hug.