Invitees not found in iCal event

Hello Rod,

Thank you for participating in the Apple Support Communities.

It sounds like your girlfriend isn't able to invite someone to a calendar event on her new iPhone 6. This option should still be available if the calendar account she's using supports it.

iCloud, Microsoft Exchange, and some CalDAV servers let you send and receive meeting invitations.

Invite others to an event. Tap an event, tap Edit, then tap Invitees. Type names, or tap to pick people from Contacts. If you don’t want to be notified when someone declines a meeting, go to Settings > Mail, Contacts, Calendar > Show Invitee Declines.

From:

Invitations - iPhone

All the best,

Jeremy

When you choose which calendar you want to add the event to, it must be one of your iCloud-enabled calendars - not local to just her phone. Once you choose that (and you can make this a default in Settings>Mail,Contacts,Calendars>Default Calendar), then the option for Invitees will appear for the event.