Delayed for 6 hours then cancelled causing me to miss flight to Europe

I recently planned a trip to Europe and noticed it was cheaper to book a ticket from Melbourne to Singapore, then a separate one from Singapore to Stockholm instead of direct from Melbourne (how I would pay dearly for this).

Anyway, I arrive on time at the airport and check in and am informed the flight is delayed one hour due to technical issues. I think this is fine since I have 8 hours in between my flight from Singapore. However, this was to repeat every hour for the next 7 hours until eventually my flight was cancelled. There was a mad rush to get to customer service who informed us that people on connecting flights or partner airlines would be booked on the next flight. I was told by the staff though, that even though finnair is a partner airline I could not be booked onto the next flight because I had booked a separate ticket for it. But they told me travel insurance would cover it. They also told us they would pay our expenses getting to the next flight the next day and home. So I go home in a taxi (costing $50) and go back to the airport (another $50). I also called finnair to tell them I cannot make my flight, but they tell me I have to book a new ticket under the terms of my ticket (??!).

Ok-ay whatever. So I had to pay $2000 for a new ticket to Europe, but I could of saved so much more money if jetstar had only told us the flight would be cancelled, as I could of just gone with another airline. Furthermore, I sent in my receipts the day I left (July 8th) for the taxi and they never issued me a refund. They also sent me an email saying I would get a $100 travel voucher from them, but I only was given a $50 one. To top it off, I checked my travel insurance terms and conditions and they cover flight delays caused by weather, but not by technical faults (which this was). So because of jetstar, I was out of pocket over $2000.

an update on this: I received a letter from Jetstar today saying they will not reimburse my taxi fare (contrary to what their customer service staff told us at the airport) because providing a plane on time goes outside my "contract" with them. What the??