Am I in danger?

Hi, to all, on my first steps here.
My wife came to Europe with her daughter 3 years ago. They retreated into the kids room immediately as, supposedly, this is the custom in Asia.I hardly saw them.
Straight away my wife had terrible mood swings and a frightening temper.
She rejected all my friends and refuses to meet them, even.
She started screaming abuse and obscenities practically daily.I am having multiple affairs with many women and even men, according to her. I cannot say hello to any neighbours as this will set her off. A phone call from my sister and I won't see her for weeks. She has hit me with a brush until it broke, then continued with a remote control, she chased me with a knife and I pushed a suitcase in front of her ( her suitcase is always there for her to escape), she swung at me twice with scissors and only inches away from drawing blood and she threw a plate at my head, also missing narrowly.
She talks often about me dying and sent my sister a message from my phone about her poisoning me.
She has urged me to commit suicide and leaves razor blades in the bathroom sink.
I can't get any help from the authorities as I think they take her side.
The police have been 3 times, once we had a fight because I supposedly disconnected her PC and phone, the second time because I supposedly stole her bank card and withdrew money 70 km away. She got the police as I tried to wrestle the papers away from her to retrieve the money. Only last Saturday they came again because I pushed her out of the room as she was damaging things, as I slept.
My main reason for being here is to help her and especially my step daughter.
My wife's mother is mentally ill and her grandmother was also. I f I can help I would for the little girl's future. My wife's family will do nothing to help and I feel they are also " a spanner short of a toolbox". I know many will think I should be "on my toes and running" but I want to help that little girl.
If anyone has advice to offer I am grateful.

Start recording things. Voice or Video. Even write-down each episode.
Then go visit a Psychologist/Psychiatrist to take their help. In more strict way, approach a mental institution and request their help.

Hopefully she needs to be treated (if she is really ill as you say).