Racehorse trainer and point-to-point champion Richard Woollacott took his own life after discovering his wife was having an affair with a jockey, an inquest heard.
Mr Woollacott, 40, was found hanged in a barn at his north Devon home in January 2018.
He had discovered a series of sexual messages to his wife Kayley on Facebook three weeks beforehand.
Mr Woollacott had also been struggling with depression and pressures of work.
Devon assistant coroner Alison Longhorn recorded a verdict of suicide at the inquest at County Hall, Exeter.
Mr Woollacott was found on 22 January at Rose Ash near South Molton by his mother Carol and sister Marie.
His sister said he had discovered a number of "sexual texts" between his wife and the unnamed jockey.
"Richard sacked the jockey and said the relationship [with his wife] was over, but he later found messages on an iPad saying the relationship was continuing," she told the inquest.
"He was hurt and humiliated."
She said he had been prescribed anti-depressants in 2017 after the death of a friend who had been riding one of his horses.
His wife told the inquest that Mr Woollacott, who she married in 2013, had been "fun" and "we got on very well".
But the couple "started to struggle" with pressure of work and finances.
"Cash was tight and the work pressure was enormous," she said, describing their relationship as "volatile".
She said the personal messages which her husband found on Facebook were "inappropriate" with "sexual innuendos".
The couple started marriage counselling and the evening before he was found dead they had said they loved each other.
A letter later discovered in his house said she and their daughter were "the best thing that ever happened to him".
Mr Woollacott produced 60 winners - including two at Grade 2 level - since he began training in 2008.
As a successful point-to-point rider, he also won the Devon & Cornwall Championship nine times and the national title in 2010.