When she awoke at 4.30am Friday to find him in the lounge with a mate, he told her he would come to bed shortly. But when she awoke again at 7am she found him still up, making school lunches for the children in then kitchen.
In her statement to police, she said her partner had stayed up all night drinking.
That afternoon she went to a neighbour's house and he turned up later, carrying a box of Cody's pre-mixed bourbon drinks, with one missing.
The couple decided to go to the beach after the children finished school that afternoon.
They arrived at Himatangi Beach about 3.30pm, with the man drinking at least two cans of Cody's on the way.
At the beach, the man and a friend went to gather pipi. He stripped off, waded in and dived under the water when it was up to his hips.
His partner told the inquest he was swimming around and seemed to be alright, but she thought he was "silly" to be in the water.
The calm water then changed colour and began to get much rougher.
When she lost sight of him, she initially thought he was joking around by hiding under the water. But after a couple of minutes, she and the friend grew worried.
She returned to the vehicle to phone emergency services while the friend went into the sea to search for him.
Ten minutes passed by the time she was off the phone and it took another 10 minutes for police to arrive.
Police told the inquest that neither the man's partner nor his friend made any attempt to seek help on the beach, and were critical of the friend for failing to alert police of the urgency of the situation when they arrived.
Palmerston North volunteer surf lifesavers found the man unconscious in murky water about 100m offshore, 2km down the beach from the surf club.
They tried frantically to revive the man for about 20 minutes, but it was too late.
A Coastguard volunteer told police they had smelled alcohol on the man's breath as they tried to revive him.
In his finding, Mr Scott said the man had been caught in a rip and taken out to a point just beyond the breakers.
He said the man had consumed a considerable amount of alcohol and was obviously impaired, which was undoubtedly a major contributing factor in his death.
"Had he been sober he may not have entered the water at all or if he did he may not have got into difficulty. At the very least his chances of survival, if and when he got into difficulty, would have been much higher."
Mr Scott found the man gave himself "little or no chance of survival" by going into the water drunk.
While his partner could have got help from others on the beach or stopped him going into the water, Mr Scott found she was not to blame.
Mr Scott said it was important the findings were made public to lessen the chances of similar deaths occurring in the future.