SOLVED. Man in a mental institution. [s]

[Vanna]

I read this book years ago, and I'm pretty sure it's a pretty old book now. All I remember is that a man is in a mental institution (he may have been a writer). He may have also been married. He keeps having these delusions or dreams where he goes to a alien world, and tries to survive there. He find some out that there's some other creatures living there with him. They're a mix of two animals. (Might of been a cow or rat) when the moon/sun turns red, those creatures end up killing each other brutallly. Whenever he comes back into his sane state, he would talk about doctors or patients, mostly a female patient. She's there because she needs to or just feels the need to behave like a child. I can't remember anything else.

[Ingo]

Probably not the book searched for, but it may pop up in lists with this book:
Red Orc's Rage.
A detailed plot description (which might spoil the book) can be found here:
Wikipedia Entry for Red Orc's Rage.

Another book in that direction, but certainly nothing like the plot you mention:
I Never Promised You a Rose Garden.

It might be worth searching for lists with this books. Although I just tried that here on Goodreads and came up empty, sorry.

[Etta.n]

Briefing for a Descent Into Hell possibly? The travel to an alien world where animals killing each other and him processing grief through understanding the phases of the moon is one of many things that happens, also plants communicating with each other, he himself developing a critique of universities and stuff...

[Vanna]

Etta.n wrote: "Briefing for a Descent Into Hell possibly? The travel to an alien world where animals killing each other and him processing grief through understanding the phases of the moon is one o..."

Thank you! That's the book I was looking for.

[Ingo]

Wow, that was a fast find!
Great, thank you all, one more for my TBR-pile.