Surprise Trip of a Lifetime

I'm newly diagnosed in my journey and my biggest trigger is sunlight. My in-laws surprised us with a trip to Australia during April. I live in a moderate climate in USA. I can't imagine not going, but I also don't want to go at all. My medications are still being worked out. AUS is hot then. I don't think I can physically do it. However - I couldn't afford this on my own...ever! I have always wanted to go.

Advice?