This is completely personal, some, all or none may apply to you, please forgive me if I say anything about myself that is wrong or offensive applied to you.
I’m in a similar boat of age and (for me) thankfully “as resolved as can be” mental smashup. Applying to university as a mature student.
I shan’t have a pack of young mates to knock about with, or university hair-letting-down or self discovery. I shall always be a stickout in my cohort and I expect CVs will be seven flavours of excruciating.
All of that passed me by, snow of yesteryear or rosebud-gathering or whatever slightly overdone metaphor the poets have come up with since the madrigals and Old French laments I grubbed those out of were written.
What you can’t lose is the love of learning that drew you to consider university in the first place. I can’t help with mental health but when you can, study.
Why are we here on the Student Room except that we have the great gift of curiosity and a decent enough brain to use it?
For me it’s Nature, especially plants and invertebrates but all of it, living or purely physical. It’s been my friend in happy days as a promising pupil and awful days in hospitals, the scrubbiest little “weed” or hated “bug” is exquisitely beautiful to me, the snow-algae on the glaciers I have never seen but hope to and the hardy Ceratodon or Pleurococcus and teeming isopod crustaceans on institutional concrete and chipboard.
To study it is gift enough, to be allowed to spend four years in it and among it as our blessedly mad government seems to be willing to lend me money to do is a daft, impossibly wonderful joy. More than I ever deserved.
There’s a scene in a very dark TV drama called “The Terror” (18 plus, trigger warning for suicide, chronic illness, mental health, graphic violence and cannibalism, please don’t watch unless you are sure it won’t cause any problems) in which a ship’s naturalist is dying in very unpleasant circumstances and as he does, the plates of his 19th century floras and medical books flash through his memory in a pure white light. I fancy a heaven would look like that, everything laid out in ordered form to be studied forever.
Find something you love that much and study it. Scrape the dust off qualifications, resit if you have to, work hard and love the work. It has made me happy, or as happy as I can be, I hope it may you.
It’s why we’re here, to learn. I accept what will never be and glory in what is still to be discovered.
All good wishes.