It is imperative that on a daily basis you keep in contact with your Thai partner to help show the relationship whilst you are back in Australia and one of the best applications that can be used is http://www.whatsapp.com/download/ and the reason is it is free and it records daily chat and also messages so no more excuses that you cannot record your daily contact with your partner at the moment this is one of the most commonly used applications.
The photo shows a relationship that is only 6 months old and the bulk of this documentation is from Australia and is from the application whatsapp, so now you have no excuses not to show contact information.