Hi, when i first went to visit my now fiance, in 2015, we werent officially in a relationship as we had only been talking on skype and whatsapp so I wrote down that I was visiting a friend. I got a letter from him saying he would be providing accommodations for me and we gave an itinerary of roughly things we had planned on seeing around Sydney (we did a harbour cruise, visited a petting zoo cant remember the name, etc). After meeting and hitting it off we decided to be in an exclusive relationship so any visas from there on I wrote down i was visiting my de facto partner. I think if she provides evidence of genuine turisty things she wants to do/ and evidence of only a temporary stay, eg. she has a job to go back to after her visit, it should be fine.