It is difficult to offer general advice to adults with autism because it is a spectrum disorder. There are a number of organizations that can assist with caring for your daughter and helping her socialize. The general answers that I can give to help you daughter is to get her involved in numerous social interactions and physical activities to promote her social skills. Finding groups that are out there that will help your daughter meet other adults with austism will help her and you build your network of support. The youtube video watching should be monitored to make sure that the behaviors being viewed are socially acceptable.
The idea of drama, music, sports, programs is an awesome one, I know there are different day programs that can help with management while you are working. I wish I could be of more assistance with resources in Australia, however I did find a few resources online like http://www.asan-au.org/ . These type of organizations are normally very willing to help you find the resources to help if you contact them. Overall, my advice to you would be to attempt to allow your daughter to get as much appropriate socialization as possible and for the both of you to attempt to build your network of support. There are many people out there that want to help you and there are many people out there that can learn from your experiences. Good luck with all that you do!