If you are looking for something to do the morning of the wedding day, go check out the Highlands Street Fair!

highlandsstreetfair.com

It's worth a drive to Longmont to visit this fantastic French inspired cheese and sundry wonderland:

cheeseimporters.com

Fun, slightly obscure things to do and see in and around Denver:

atlasobscura.com/things-to-do/denver-colorado

Some good options for day trips:

uncovercolorado.com/best-day-trips-near-denver-co

If the sand dunes aren't on your bucket list, they should be. Almost a four hour drive from Lakewood:

nps.gov/grsa/index.htm

Camping/lodging at the dunes fills up immediately, although you can get a permit and camp on the dunes themselves. The towns of Crestone and Salida are within 90 minutes of the dunes and are great places to visit.