If you were married but have been separated for 20 years are you still entitled to half of the marital assets?

If you were married but have been separated for 20 years are you still entitled to half of the marital assets?
My boyfriend. Of the last 6 years is still married. To someone. But they ha e been saprated for the last 20 some years he has stage 4 colon cancer and has been put on Hospice. And has 6 months to live all the things we have got me and him got together can she take it. From me