My dad was cremated. His wife but legally separated took everything in dads apartment and left us nothing We want some of his ashes but she refuses.

I suggest speaking with a probate attorney who practices in the county where your father lived when he passed away.  Lawyers on this forum cannot directly reach out to you, you will need to initiate contact.  You can use the Find a Lawyer tab on this webpage, check with a local bar association, or ask friends and family if they can refer you to an attorney. I'm sorry for the situation you find yourself in.  Best of luck in working through these issues.