Mrs O'Brien - who described the trip as a "holiday in hell" - was among the 300,000 visitors stuck in Bangkok after anti-government protesters shut down the Thai capital's two main airports.
Another New Zealander, Katrina Coleman - whose two-hour transit stop in Bangkok turned into a 10-day ordeal - only managed to return home to London where she now lives after buying new tickets to fly via Paris. Direct flights to Britain have still not been resumed.
Mrs O'Brien and Ms Coleman are worried whether they will be covered by insurance.
Like thousands of other tourists, the women were unaware they could claim at least some money back from the Thai Government.
Under the scheme - part of a proposed 2.4 billion baht plan by Thailand's tourism ministry - they could have received subsidies of up to 2000 baht ($100) a day for their accommodation and food bills.
Details posted on the websites of the Thai Ministry of Tourism and Sport and the Thai Hotels Association state tourists who could prove their flights had been cancelled during the blockade - by showing their air tickets and passports - could get cover.
However, travellers needed to show beforehand that they were stranded in order to claim the allowance later.
"Thanks to Bangkok, it looks like I'll have nothing left to spend over Christmas after blowing out my credit card," said Mrs O'Brien.
"If they [Thais] were really genuine about the scheme, they would be doing far more to inform stranded tourists rather than just posting it on their website."
Most stranded tourists would be unable to claim their expenses against their insurance, because of exclusion clauses, said Dave Lim, a product manager with Tower Insurance.
"Most policies will not cover claims for losses arising from civil war or political uprising."