How the farm gets split up in divorce depends on state law.  In some equitable distribution states, if you put money into the property, it can be regarded as converted to maritial property, and you may get some.  In other states, there may be a formal procedure as to whehter this can be treated as community property.  It may be difficutl to prove what you contributed money for? 

Many states have provisions that he cannot throw YOU out with no notice.   No ideas as horses.

He owns the house, but legally he can't remove you until the divorce is final. Would you want to stay there? Or start saving up, and give him excuses why you can't pay for stuff. Meanwhile I would get a storage locker, and start putting things in there. Pay cash for it, and put stuff in there he won't notice. After what he put you through I'd probably sell some of his stuff he won't notice for some time. I wouldn't tell him for sometime until all your ducks are in a row. I did this in my first divorce. Can't tell you how grateful I am today, a good lawyer helped me and at 62 I'll be getting ex DH's retirement because he died. Seriously act nice, and put a nice poker face on. That's your best avenue imo.

For sure get all important documents out of the house.  If you find anything that is not ours but has powerful informatio on it get a photo to doc app for your phone and takes pics of everything. Or take it and photo copy it.  

My XW moved out of our home a few weeks after telling me she wanted a divorce.  She took only her clothes and a few small appliances.   She left all of her college papers including every project and report she was assigned during her last three years of college.  The originals were all in my and writing and the graded typed copies were verbatim what was in my hand writing on the drafts.   She also left her diary.  Those two treasure troves of information handed me nearly complete control of asset distribution in the divorce since every nasty detail of her academic fraud and distinguished career as a caver crotched adulterous whore were handed to me on a silver platter.  The diary of course was in her hand writing.  I made several copies of everything and had the copies notarized.

So copy everthing and know it all inside out and backwards.

Plan, prepare, then execute to the plan.

Enjoy your new life.

Really good advice above. My question is I'm wondering why it would take months to go through everything. After having your legal documents, family photos, and basic essentials, what else is truly worth dragging out this process? My dad stayed with a very evil person way too long mostly because it would take him too long to leave. Wanting to take so much of his stuff weighed him down. When he finally did, it was because a cop told him he should cut his losses (when HER crazy ass called the cops they ended up being supportive to him lol) he said it was the best decision he could have made to leave 90% of his crap behind. If your DH is the type of person to be vindictive and mess with you or your things once he knows, I would be extremely selective on what you feel is needed. Besides, it does feel good starting from scratch.

The animals would be my priority as well.

The fact that you've inherited your father's estate can work in your favour. Obviously you have to go through it and decide what to keep/throw etc so it won't look like odd behaviour when you're sorting through stuff, boxing it up and making lists. Except it won't just be your dad's stuff.

Be systematic. Go through it room by room. Rent a storage facility and use it to store stuff you want to keep. Tell SO you're throwing it away but actually you're moving it to safety ahead of time. As you go through each room, make a list of stuff which you need to leave for the moment to keep up appearances. When you actually do move, you won't be panicking and forget stuff because you'll already have it written down and you'll know what you need to collect and exactly where it is.

Make sure the important stuff has already gone. Because your priority on your moving day will be the dogs and horses. Assuming your DH works however, you plan that move to start about an hour after him leaving for work. If you have a couple of people who can help that's even better; you can give them the list of what to collect from each room whilst you concentrate on boxing up the horses.

You don't even need to tell DH unless you want to; your absence will speak for itself.