You need to start putting things in order to leave. Gather important documents like your birth certificate, social sec card, stuff like that. Do you have your own bank account?

Just because he has DID does not make it okay for him to hurt you and your pets. Having a bad childhood, having a bad day at work, having a mental illness - none of that makes it okay to hurt you.

Do you have someone who can take care of your cats for a bit? If not perhaps it would be best to ask the animal shelter if they can take them until you are able to care for them.

You need to know that you are most in danger of serious injury when he realizes you are leaving. Does he have weapons? Do you have a plan for where you will go? Do you know where the domestic violence shelter is? Do you know how to get a restraining order?

Domestic violence hotline ----> http://www.thehotline.org/get-help/ (not sure where the help is in your area but this one should know)