Mr Marshall has done everything in his power to warn governments about the disaster unfolding in the Southern Riverina.
He could see neighbours walking off their land in despair, or being forced to sell the herd they loved, and now he is in the same position.
"These cows are everything to our family," Mr Marshall said.
"Four generations have bred these cows."
He said the emotional toll is beyond words.
"They're incredibly hard working cows, they're incredibly high production cows, but unfortunately I just can't keep them and that's really sad.
"I feel like I've let them down."
Mr Marshall was part of a delegation that met with the Prime Minister before the election last year, and Scott Morrison gave hope that he would step in and try to help.
He now feels as though his advocacy efforts have been in vain, as politicians make it clear they don't care for his family or other farmers in the region.
"Unfortunately, we haven’t been able to make Governments aware of the crisis, despite our best efforts.
"It’s devastating for our family and employees to be treated this way."
Mr Marshall said the situation is avoidable, yet no-one has helped.
"Don’t even get me started on [Federal Member for Farrer] Sussan Ley; all we heard during the election campaign was how much she cares about water, but once she was re-elected we’ve heard nothing, and she’s done nothing," Mr Marshall said.
"Even my 11 year-old daughter wrote a letter begging Mr Morrison to show leadership and help our region, which I hand delivered to him.
"I guess she’s like the rest of us; we don’t matter to the PM now he’s safely back in his job."
Mr Marshall said he could not explain the frustration at the lack of support for this region from politicians.
"[Water Minister] David Littleproud has his precious Basin Plan which he wants implemented without political bunfights; I suspect he sees it as a giant tick for his career prospects.
"It appears we have politicians who are prepared to sacrifice our region for their political careers.
"If that was not the case they would be here talking to us and finding the solutions we need."
Mr Marshall said leadership is required for the survivability of the industry.
"Since the election we haven’t seen Littleproud, it’s all too hard for Sussan Ley and the Prime Minister is no longer interested." he said.
"It is frustrating beyond words."
Mr Marshall has hoped for change to irrigation along the Murray to stop any further damage to his, and other, dairy farms.
"We'll batten down the hatches and fight on as best we can, but I suppose once you start on this direction, unless we see some light at the end of the tunnel one of the options it to continue to disperse."
The future of farming industries in the Southern Riverina require irrigation, and Mr Marshall said if politicians use the water efficiently their problems would be solved.
"It looks like we could be the next in line to be put out of business by politicians who don’t care," he said.
"The tragedy is, we won’t be the last."