The reason your visa hasn't been approved yet could be that, in view of the growing tensions, the consular staff are apparently fully occupied with preparing evacuation plans for Thai citizens and the consulate itself. I can well imagine that ordinary visa applications are simply not a priority.
Short update: In case of a conflict the thai embassy might stay open but the consulates will close for sure. Keep this in mind. And I just read that the expenses are killing you. If you have to leave, the most cost effective option would probably be to take the bus to Savannakhet, Laos and reapply there, as accommodations there cost around 300 to 400 baht and food is also very cheap. I got my visa there within three days. Since Savannakhet is right on the border, once you have received your visa you can simply take a bus across the Mekong to Thailand and from the Thai border town of Mukdahan you can take a bus to any place in Thailand for a few hundred baht.
Tensions between Thailand and Cambodia are rising. I suspect there's much more to this than we can currently imagine. Stay and wait, but develop an escape plan to Laos or Vietnam, so you can reapply there if fighting breaks out.
Ask your Australian bank if they can generate a letter for you stating that the balance in AUD is equal to the value X in EUR. At consulates they always want to see something official, with a stamp and a signature.