Hi Ben,
For my understanding, you want to share the calendar and contacts between your two users.
If this is the case, please follow the steps below:
1. Connect to your exchange account via powershell:
a. $cred=Get-Credential
b. $Session = New-PSSession -ConfigurationName Microsoft.Exchange -ConnectionUri https://ps.outlook.com/powershell/ -Credential $LiveCred -Authentication Basic –AllowRedirection
c. Import-PSSession $session
2. Create a shared mailbox:
You can set full access permission to this shared mailbox, so that the contacts in this shared mailbox can be reached both of you.
http://technet.microsoft.com/en-us/exchangelabshelp/ee441202.aspx
3. Share your calendars between your two users:
Set-MailboxFolderPermission -Identity user1:\Calendar -User user2 -AccessRights ReadItems
4. For more information, please refer to these two links:
How to connect with your exchange account via powershell: http://help.outlook.com/en-us/140/cc952755.aspx
Set-MailboxFolderPermission: http://technet.microsoft.com/en-us/library/ff522363.aspx
Thanks,
Jason Jiang