The shit they put O'Brien through on DS9 is just insane.
Its funny to me that the real reason he gets especially picked on is because he is played by such a talented actor. I loved DS9 but Colm Meany is by far the best actor on that show IMO.
TNG in particular did a great job of stretching the characters by building them up to a definitive version and then showing us, in one way or another, a variant or situation that completely shatters that image. Data and Lore. Alternate Riker. Broken Picard. Troi and Lwaxana. Worf and also Worf but later.
I'm really torn on whether or not I think The Inner Light should've had more of an effect on him.
The crux of the issue is that in his actual life he was a career guy who never made time for a family.
So, on the one hand, living that life could've fulfilled his dream and made it so he could dedicate himself to being Starfleet with no regrets. In a real way, he got to have both.
But on the other hand, if he dismisses that entire life as a hallucination and doesn't embrace how it felt, it could make his longing-for-a-life-he-never-had that much worse.
Seeing as we never saw him have a complete breakdown over it, and only mentioned it later on in First Contact that he had any regrets about being the last Picard, I can only assume the former was true. (Leaving aside Generations. Why are the odd-numbered Trek films always so goddamn weird?)
Um....pretty sure Deanna Troi was the one giving therapy to Jean-Luc. And she saw some shit during that voyage. Seriously, she needs her own counselor.
I think it's implied that DS9 had multiple counselors but they just aren't bridge-level personel. Ezri later becomes the most prominent counsellor but we also see O'Brien going to therapy with Telnorri, so it's implied the station does have dedicated mental health staff.
I would say that technically should give DS9 the upper hand, but Miles' experiences with Telnorri aren't exactly great and it does seem like DS9 is always given the bare minimum by Starfleet.
The minstrel boy to the war is gone
In the ranks of death you will find him
His father's sword he hath girded on
And his wild harp slung behind him
"Land of Song" said the warrior bard
"Tho' all the world betrays thee
One sword, at least, thy right shall guard
One faithful harp shall praise thee"