20 years with a psycho
for all those who can and it is early in the marriage and the kids are young - get out.
get help in gathering the evidence of what is happening and then divorce. no matter what happens, it wont be worse than staying. this is especially true of the kids. trust me, some or all of them will become just like her. its worth the risk to help them escape. get the hell out as clean as you can. if you do it right, she will get very little visitation, hopefully supervised only.
to get her to perform/escalate for documenting - dont resist her. let her come out. do not let her manipulate you at all, even if it means not doing some things you normally would as a decent human being. never retaliate. get some recording going on. check your local laws on that. hire professionals if possible.
because i guarantee you, she will not be the same person you live with in court. your kids are being emotionally abused. put a stop to it before its too late. do it intelligently. win for your kids.