How do I protect myself if divorce is a possibility?

Hello, I am a total newbie here and need help. I reside in California, USA. So I've been married to my wife for about half a year, dated for a year. Things took a turn for the worse recently, then took another. We've argued more in the past few months than we have in our entire relationship and it's really starting to hurt us. She's called for a divorce (whether seriously or not) during our arguments several times already, and I've been the main one pushing to resolve or compromise. But she has said it too many times now and I have to cover all my bases.

I am a very simple man and just want to live a happy life. I don't want her money or anything like that if it really does come to it, I prefer an uncontested divorce (if I understand the term correctly), just no muss no fuss let's just all move on with our lives. But in case she tries to come after anything I have, are there any precautionary steps I need to be taking? We didn't do a prenuptial (my best friend dancing his I told u so dance alrdy). We're currently living at my place where I hold the title myself (bought long before we married) have been paying mortgage myself out of my own bank account, in fact I've been paying for almost everything (wedding stuff, new furniture, new house things, the works - which I honestly don't mind, just pointing out in case it makes a difference in something). She owns one property under her name only (also bought before we married) and lives off of the rent from it, she hasn't worked for almost a year. We have a joint account that I myself have put money into to meet the minimum balance, aside from that we haven't jointly signed up for anything else together that I can recall. We have no kids but we did just start trying right before these turn of events and she's currently not pregnant.

Is there any general advice for me to protect myself should anything occur? Or start keeping track of (ie conversations, expenses) or anything like that? I have a small voice recorder I can keep in my pocket, but can something like that even be used in court? Will setting up discrete video cams around the house be necessary or even legal? I do train in my spare time in Muay Thai so I'm worried she'll go as far as claiming domestic violence on me (and as I've heard women are favored strongly there). I've never laid a hand on her even in the emotional parts of our arguments nor will I ever, but how can I uphold that if it ever gets to court? What kind of things would be considered evidence in my defense? I've witnessed her faking fear first hand so I can definitely see her faking some kind of fear of me if it goes to court.

I'm still holding out hope it doesn't come to this but things have changed so drastically in the past few months, she's honestly not the woman I married anymore. I'm worried and just want to protect myself. Appreciate any advice.