Neighbour Theresa Mitchell said she tried to help the young mother, who suffered burns to more than a third of her body.
“She was sort of staggering across the road, towards here, screaming my name… screaming for me to help her,” she told Nine News Perth.
“I was going to hose her down, but that wasn’t going to work so we brought her in tried to keep her under the shower, she wouldn’t stay there so we laid her on the floor and poured cold water on her until the ambulance could get here.”
Ms Mitchell said the woman begged her to take her pain away.
Mr Bolderson is due to appear in Rockingham Magistrates Court on Wednesday via a bedside hearing.