If you were legally married as of Dec 31 2020 you can only file married (Jointly, separately, or Head of Household if you qualify).
Ask your attorney if the " Dissolution of Marriage" means that you are legally not married. That is a legal question, not a tax question.
**Disclaimer: This post is for discussion purposes only and is NOT tax advice. The author takes no responsibility for the accuracy of any information in this post.**
