While I understand your fear of dealing with ex, in reality you don't have to contact your ex.
You have to hire a family lawyer and communicate with ex exclusively through lawyer. This is what they're paid for.
What's really scary is the fact you're still married to the person who can harm you. If you live in community property state like California, your ex may be opening new credit cards or getting big loans. And you'll be liable for those! That's a really scary part. Or if they get extra tax benefits by providing false information to IRS on your behalf.
You should really seek divorce, there's nothing good about being married to abuser.