I don’t know any details but he had some tough times. His wife divorced him about when he was ready to retire and he tried to prolong his career but he just didn’t seem to have it anymore. 65 is young.
Cancer, from what I heard.
As a big Cubs fan - and while I don’t know anything first-hand (of course) - this isn’t quite accurate.
Ryno married his HS sweetheart. She... well, again, I don’t know her... but slept around on him a lot (rumors say Davey Martinez, Raffy Palmeiro, and others).
Ryno was on the back-half of his career, but this all came to a head in 1994. She divorced him - there was also the strike - and Ryno just hung it up because he was in a bad place and wanted to be with his kids.
He met his now widow - Margaret - shortly after the divorce (IIRC, she was also a divorcee with a couple kids). It was a much healthier relationship.
It wasn’t that he *couldn’t* play - it was that he a personal hell to deal with and he wasn’t in a place where he felt he could give it his best.
In a better place in 1996, he came back - the story is basically that he was a spring game with his new wife, his kids and stepkids, got a big ovation at a spring game, and Margaret and the kids all said “You want to get back... and you should.” So he did.
Despite the year and a half layoff - Ryno came back in 1996 posted 3.2 WAR.
I don’t know Ryno (though, I got to drive him from the airport once after he retired — long story), but he was a very private and shy guy. But a *good* man and a helluva ballplayer.