Lord Euston was regarded as rather a nasty person with most contemporaries seeming to have avoided mentioning him. The main reason for his reputation was the way he treated his wife. 
In October 1740, while still engaged to Lady Dorothy Boyle, they attended a ball given by the Duke of Norfolk where he treated her with public contempt. While at a dinner they attended, he shouted at her across the table, "Lady Dorothy, how greedily you eat! It is no wonder that you are so fat." She blushed and started to cry. 
However, Lady Dorothy--pretty, good-natured and gentle--had fallen in love with him when only sixteen years old. Nothing could prevent Lady Dorothy from marrying him and, after the marriage on 10 October 1741, Lord Euston forbade his mother-in-law access to his house which caused a scandal. What happened in the seven months of their married life is not known, but after seven months she was dead. 
Her mother painted her portrait and placed underneath: Lady Dorothy Boyle, born May the 14th 1724. She was the comfort and joy of her parents, the delight of all who knew her angelic 
(sic) temper, and the admiration of all who saw her beauty. She was married October the 10th, 1741, and delivered (by death) from misery May the 2nd, 1742. 
Apparently he also terrorised his father's tenants. When one came to Lord Euston to pay his rent, the latter maintained that three shillings and sixpence was missing. The tenant claimed it to be 
correct but would check the amount, meanwhile quite happily paying the amount in question. In a rage, Lord Euston threatened to have him removed from his estate. The tenant--a father of six children, not knowing that Lord Euston had no influence on his father, the Duke of Grafton--went home and shot himself. 
It was with great relief to almost everyone when the childless Earl of Euston died in 1747. 

Source: Leo van de Pas