Sync iPhones, don't want to create 3rd apple ID

I want to sync my iphone calendars and reminders with my husband but want to keep our iTunes purchases separate. How do I do this? Also can we share one iCloud.com address? (Like, how do I add my apple I'd to this the icloud address?) we really don't want to have to create a 3rd apple ID so he created an iCloud address and thought we could add my apple ID to the cloud somehow.