Ordinarily, you can go to the country clerk's office in the county in which the case is pending. Simply check the Plaintiff's index cards and you will find his name there. If not, then he doesn't have an action pending there. Why not just ask to see the divorce papers? He should have a copy of them, or he can get them from his attorney.
You could get a day pass to Lexis/Nexis - but it wouldn't help. A check of the open cases in the relevant county courthouse should be sufficient to determine if he has filed for divorce. Some courts have those records online and searchable by last name.
The Colorado Judicial Branch maintains a website that lists courts by county at http://www.courts.state.co.us/Courts/County/Choose.cfm. Go to this webpage and click on the county in which your boyfriend lived with his soon-to-be ex. Then search the docket for the case.
The information provided to you in this answer is not, nor is it intended to be, legal advice. You should consult an attorney for advice regarding your individual situation if you have further questions.
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