irs.gov

Lots of info.

Separated or divorced taxpayers.

If you were separated or divorced prior to the sale of the home, you can treat the home as your residence if:

If your home was transferred to you by a spouse or ex-spouse (whether in connection with a divorce or not), you can count any time when your spouse owned the home as time when you owned it. However, you must meet the residence requirement on your own. If you owned your home prior to your marriage and after your divorce or separation, and your spouse or former spouse is not allowed to live in the home under a divorce or separation agreement, you count any time that you owned the home solely or jointly with your spouse as time when you owned it, and you must meet the residence requirement on your own.