[Lizard]

It's possible to email tasks to someone else if they use Mail as their email client and have the Mac edition of OmniFocus.

All of this is configured in the Mail tab of the OmniFocus preferences.

[√] Add Mail Rule to create OmniFocus actions

Put your fiancé's email address in the "Allowed From addresses:" list on the right.

Choose which option you want for processing messages, and let your fiancé know, so he can create emails that will correctly be picked up by the system.

For more details, I recommend reading the "Processing Mail messages into actions" section of the help.

Does that help?