I suggest you refer to IRS Publication 590-B, Distributions from Individual Retirement Arrangements (IRA).
https://www.irs.gov/forms-pubs/about-publication-590-b then click on the Publication 590-B link.
This explains situations for IRA Withdrawals.
Since you are still legally married, it is likely your tax filing status will be married. Refer to https://www.irs.gov/help/ita/what-is-my-filing-status and click the "Begin" button at the bottom of the page to determine your filing status.
(What follows is not tax advice, it it personal advice.) I suggest you find an attorney and begin divorce proceedings. Explain your situation and see if you can find an attorney to help you now and get paid later, or perhaps get someone to help you at a reduced rate. If you live in a community property state, you are entitled to and own half of the assets, income and debts of both spouses acquired during the tenure of your marriage, regardless of who earns it or purchased it. This includes IRAs. According to https://www.quickenloans.com/learn/community-property-states community property states include: Arizona, California, Idaho, Louisiana, Nevada, New Mexico, Texas, Washington and Wisconsin. In these states, any assets acquired by spouses throughout their marriage is labeled as community property, regardless of who buys it. California, Nevada and Washington also include domestic partnerships under community property law.
If you live in a community property state, half of your spouse's income is yours.
My advice: Do what it takes to get a lawyer and get moving on your divorce. Get an interim court order to obtain your portion of your spouse's income, even if it means garnishing wages.
(End of personal advice.)
