Q: If a spouse leaves their job and therefore their insurance, then gains new job and insurance, is ex spouse still covered?

A: see: http://webserver.rilin.state.ri.us/Statutes/title27/27-20.4/INDEX.HTM

" (a) In the event of a final judgment of divorce, whether absolute or otherwise, where one party to the divorce was at the time of the entry of the judgment for divorce a member of a health plan providing family coverage regulated under chapters 18, 19, 20, or 20.1 of this title and § 42-62-13, or a member of a health maintenance organization as defined in § 42-62-4(5), or any similar health plan whether regulated under these chapters and sections or not, the person who was the spouse of the party prior to the entry of judgment for divorce may remain eligible for continuing benefits under the plan and health maintenance organization without additional premium or examination if the order is included in the judgment when entered. The eligibility shall continue as long as the original member is a participant in the plan or health maintenance organization and until either one of the following shall take place: (1) the remarriage of either party to the divorce, or (2) until a time as provided by the judgment for divorce. If the person who was the spouse of a member of a plan or health maintenance organization as set forth in this subsection becomes eligible to participate in a comparable plan or health maintenance organization through his or her own employment, the continuation of the original plan coverage shall cease."

Note that there are exceptions to this rule and a consultation with a licensed family practitioner is well advised.