Advice with marriage (22F) (26M)

I (22F) is from Australia and my partner (26M) is from the US. Our original plan was to get married in the US in December of this year and then start our CR1 visa process to close the distance. After talking to my parents about that idea, they wanted me to get married in Australia instead. Mostly because my mum wants to be a witness when we sign the papers but due to obligations with being a caretaker for my grandma, she can’t just up and leave. My partner doesn’t mind doing the courthouse in Australia but we won’t be able to get married until possibly the year after next year due to a deployment (he’s in the military) and very limited time off. We both don’t want to keep being in ldr for any longer. We might as well take advantage of his time in deployment to wait for our visa to be processed so by the time he’s back, it’ll almost be done. So now I’m at a crossroads of what to do