You must file as married because that was your marital status on Dec. 31. You can file married filing jointly and include all of your spouse's information or each of you can file a married filing separately tax return. It is almost always better to file jointly than separately. See this comparison: https://ttlc.intuit.com/questions/1894449-is-it-better-for-a-married-couple-to-file-jointly-or-separ...
