You might not want to hear this, but your wife is showing all the signs of regressive dementia. I've seen the majority of the symptoms you mention, when my grandmother fell ill. You have to see help as soon as possible, especially as you could be in danger yourself. I'm not saying she would deliberately hurt you, but the situation can arise when sufferers don't know where they are, nor who they are with, and they can often lash out.
You need to see a doctor, and a social worker as well, and to get help. Do you have any children, or close family? Previous posters have listed some numbers, so I won't add to those, but make sure you do it - don't wait 'in case things get better'. Sadly, it is unlikely that things will improve, so you need to get help soon. Good luck to you both.