E.,
I have first-hand experience with this. I encourage you to pursue a civil protection order (CPO) against your husband. My attorney recommended one when I separated from my husband, and it was the smartest strategy. It kept him away from us during the emotionally-charged divorce, and it gave me tons of leverage in the final agreement. My ex was ultimately granted only supervised visitation with our daughters, and no overnights. (Incidentally, he was also an alcoholic and was on anti-anxiety/depression medication.)
The privacy act will prevent doctors from testifying about your husband's mental state, and I wouldn't involve your husband's boss unless you want him to lose his job and not be able to afford child support.
I didn't need a paper trail to get the CPO (although I could have easily produced one). I only needed witnesses. In fact, I only needed two witnesses...and one of them was my sister who only heard him threaten me over the phone once. I also testified, and so did my ex. Most judges err on the side of caution when there are children involved. Do you have any witnesses who would be willing to testify on your behalf?
I agree with some of the other moms, though -- please be careful. I left my husband first, and stayed with my parents for a few days while I was pursuing the CPO. Then the judge granted me "exclusive use" of the home...which meant my ex had to move out, and my girls & I could go home.
I would be happy to share more of my experience with you, if you think it would be helpful. Just send me a personal message on this site, and we'll get in touch.
I wish you all the best.