This is an extremely fascinating question, both in terms of what it presupposes and in terms of the date that the events you are interested in would have taken place.

Let me explain. By c.1800, the British, via their East India Company (EIC), had had a presence in India for almost two centuries, having first come to Indian ports to trade in the early years of the 17th century. For three quarters of that time, before the first significant conquests were made in the 1750s, they were engaged in a perpetual struggle to maintain what might more accurately be described as a toe-hold than a foot-hold on Indian soil. And although the EIC did eventually succeed in establish secure bases at Kolkata, Mumbai and Madras, it was a pretty close run thing.

In the seventeenth and eighteenth centuries it was not uncommon for half the Europeans scattered through India to die of fever, drink or heatstroke in a single year. In Mumbai, in 1692, nearly 90 percent of the British population succumbed to disease in just three months; in the same city, 15 years later, a mere seven men were fit for duty, and an ambassador from Persia, arriving unexpectedly offshore, had to be refused permission to leave his ship ‘lest he should relate to his master the nakedness of the land’. Even a century later, at around the time that you are interested in, an officer joining the Company’s army ‘said goodbye to his family in England knowing that there was only a slender chance that he would ever see them again’. The principal difficulty was surviving long enough to develop resistance to India’s main diseases. In any given year the great majority of those who died were comparatively recent arrivals; fatalities were most common in men under the age of 30 and women aged 25 or less. As late as the 1830s, when Emily Eden studied the gravestones filling the European cemetery at Meerut, she failed to discover ‘any one individual who lived to be more than thirty-six’.

The Subcontinent could kill in many ways. Dysentery, often carried on the wind in dust laden with organic matter, was one of the most common illnesses; typhoid was another; smallpox and plague were common, too. But cholera, the fever carried in the water, was the most feared of all diseases. This was not merely because it was generally lethal (nine out of ten of those infected with the bacillus died, the linings of their intestines eaten away, voiding as many as 25 pints of diarrhoea in a day), but because it struck with awful speed. The interval between the first emergence of the symptoms and the victim’s death might be as little as two or three hours, and corpses decomposed so rapidly in the damp heat of India that they had to be interred almost immediately. ‘We have,’ one Company officer noted in 1805, ‘known two instances of dining with a gentleman [at midday] and being invited to his burial before supper time.’ Statistics show that six out of every seven British officers despatched to the Subcontinent between 1800 and 1825 never returned, and, for all their wealth and grand ambitions, the few hundred merchants scattered across India at any given time in the 18th century were, as one of their own number admitted, never more than ‘fleas on the back of the imperial elephant.’

Given all this, we can probably understand why a high proportion of British merchants and soldiers in India were single men, why the temptation to take pleasure where it was available was often indulged, and why it was vanishingly rare for those who were married to British women to travel out to India with their wives; one of the handful of Company wives who did live in India during the 1820s confided in her diary that ‘Here people die one day and are buried the next. Their furniture is sold on the third and they are forgotten the fourth… O lord! Preserve my husband and me!’ (No such luck; husband and wife both died there.) Pretty much the only European women around, in fact, were the ‘spins’ (spinsters) of the ‘fishing fleet’ – as the single women, mostly plain, dispatched each year to Bengal by their families in search of husbands were cruelly known. These women rarely moved inland from the main Company bases, and in any case ignored their male contemporaries. This was because few Indian officers married before the age of 40, the age when most could expect promotion to the rank of major and with it the increase in pay that would at last enable them to support a wife and children. ‘India,’ one lady of Madras explained, ‘is the paradise of middle-aged gentlemen. When they are young they are thought nothing of; but at about 40 when they are “high in the service”, rather yellow and somewhat grey, they begin to be taken notice of and called “young men”. These respectable persons do all the flirtation too in a solemn sort of way, while the young ones sit by, looking on.’ The perhaps inevitable consequence was that marriages between teenaged girls and men aged somewhere between 40 and 65 were commonplace.

It was really not until the 1830s, and often rather later than that, that improvements in medical care, the development of the custom for families to retreat to the cooler weather of the hills to avoid the unbearable conditions suffered during the annual "hot weather", and – not least – a fashion for greater moderation in consumption of food and drink, made the idea of bringing a wife to India, and attempting to raise a family there, seem anything much more than suicide.

(Not kidding about the need for moderation in consumption, by the way; around 1780, one newly-arrived young officer was ‘shocked to see one of the prettiest girls in Kolkata eating some two pounds of mutton chops in one sitting’, and a peculiar craze for food fights was at its height: ‘Formerly,’ one veteran officer recalled,

‘instead of drinking a Glass of Wine with a Gentleman, it was usual to throw a chicken at his Head – while the ladies pelted with Sweetmeats and Pastry. This was thought Refinement in Wit and Breeding.’)

In the absence of European women of marriageable age, anyway (at least those actually interested in marrying them), many British officers, especially young ones, therefore took Indian mistresses (known at the time as bibis) – some of whom became Indian wives and a good proportion of whom gave birth to mixed race children. Among the best known examples was Sir David Ochterlony, a prominent Scottish general in the Company's service, who took 13 Indian wives and - it was said - paraded them around Delhi on the backs of elephants each evening. We can trace these histories, at least in shadow, through an examination of contemporary wills. These reveal that one in three British officers who died in India between 1780 and 1785 left wills in favour of their bibi, but that thereafter the practice of taking an Indian mistress began to decline quite rapidly. By 1805-10, bibis are mentioned in only one in four wills, and by 1830 it was only one in six.