How not to be sued by your Dad?

Dad had been on zoloft for the last four years since my mother died. He began to wander the neighborhood, buying guns and sleeping with knives. Things got worse when the doctor decided to take him abruptly off Zoloft. Two weeks later, on his 90th birthday he announced that he was going to sue us until we were ruined because he wanted all the stock in the family corporation to set up a foundation for single women--his caregivers. Earlier we had put up with his giving the house to one caregiver and proposing to many and "tipping" them with thousands of dollars and loaning our brother a huge amount of money. The brother, who worked on his farm, doesn't want dad declared incompetent for obvious reasons. Fearing for our father's situation, we had to go to court and I now share his guardianship and conservatorship. The brother and my father are indeed suing us--myself and four other siblings--for forcing this. My enraged father had to be returned to the house by the sheriff because my sister-in-law took him away. The doctor is against us, saying he has only mild dementia and will be using the Zoloft defense next week. Since myself and my five siblings--who have been taking care of him for the last six months--normally live far away, the community sees us the way my brother sees us--just there for the money. Dad, an ex-judge, is drawing out the legal part so our lawyers' fees are indeed ruining us and he still won't have a psych eval. We've offered my brother to be sole guardian and co-conservator but my brother wants to be sole conservator because there's lots of money involved--on their side, not ours. In the meantime, I'm trapped in the house with a furious dad and my brother, the screamer, whom the doctor says should be there because dad wants him to protect him. I am now perfectly happy to let dad wander the streets with my brother, but I need to protect my siblings' assets. Obviously we will inherit nothing as a thanks to trying to protect dad.