Despite thinking she was covered under credit card insurance, her bank refused to pay up, leaving her mother with a $60,000 bill to save her daughter.

It was the trip of a lifetime that turned into a life and death struggle, which then led to an expensive fight with a bank.

When Lyn Johnston took her daughter Jamie to Bali they never guessed a cocktail in a local bar was the beginning of a traveller's nightmare.

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The cocktail had methanol added to it, and that drink has dramatically altered the course of Jamie's life.

Jamie is living in a hospital rehab unit, six weeks into a long recovery from brain damage caused by methanol poisoning.

“My speech has been affected. My speech is very different now,” Jamie said.

Her motor skills have all been severely affected, but she's lucky to be here at all.

“I thought she was going to die. She couldn't breathe, and there was no proper medical person there to assist,” Lyn said.

Jamie needed urgent medical attention, but flying on Garuda airlines, that attention never came.

Jamie was taken off the plane and to a Bali hospital, but they refused to treat her until someone paid up front.

“They said nothing could happen until the money went into their account,” Lyn recalled.

Lyn called the Commonwealth Bank. She's been told her daughter was covered under her Gold Mastercard.

She’d been made to understand that if “you pay for your accommodation and airfares with that card, for yourself and immediate family, and you will be covered.”

But Lyn says it was only when her daughter lay dying in a foreign hospital that her bank mentioned the fine print.

“My daughter is not a dependent, and therefore not deemed to be immediate family in accordance with the policy. I have beat myself up over this many times. I should have read the fine print,” Lyn said.

Jamie had to be medevaced back to Australia. Lyn had to extend her mortgage before the medevac team at SOS Flights agreed to save her daughter's life.

“They said ‘well, you're going to have to pay for her to be evacuated to Darwin’. And told me it would be $45,350 for the jet. Nothing would be done until the money went into the account of SOS,” Lyn said.

Gerard Brody is a director with the consumer action law centre. According to him “banks should make it very clear to consumers up front what the exclusions are.

“Travel insurance is actually very complicated for consumers. Our experience is that there are many exclusions that are hidden in the fine print of policies, making it very hard for consumers to know up front whether they're going to be covered or not.”

The Commonwealth Bank refused to comment on air but in a statement said they were "very upset to hear about our customer's situation, and we always look to do the right thing. We have contacted our customer to support her claim following this unfortunate situation."

It's a back down by the Commonwealth Bank, which acknowledged in a phone call to Lyn that their credit card insurance, underwritten by Zurich Insurance, needs an overhaul.