Within Thedas, there are several different views in regards to sexuality and marriage. Common to all groups is that marriage is not primarily regarded as a romantic affair, but a duty to one’s family.
Viewpoints
The Chantry
According to the Chant of Light, Andraste had a spiritual marriage with the Maker. All Andrastian priests are therefore symbolically wedded to the Maker and cannot legally marry, though they are not sworn to celibacy. In the eyes of the Chantry, marriage is both a celebration of tradition and a practical decision. Through a favorable marriage, one can make valuable connections, improve one's social standing, and secure financial stability for oneself and one's family. Love is not necessary for a successful marriage but is nonetheless desirable, as it makes the union stronger. The Chantry permits annulments but not outright divorce.
City Elves
Among city elves, marriage is a rite of passage, the single greatest thing that distinguishes children from adults. Elven children are usually matched by their parents and the Alienage elders, and the bride and groom often will not have met each other before the marriage ceremony. Betrothals are often made between families from different Alienages in order to promote inter-city trade and relations, as well as to bring new elves into the Alienage community. Marriage ceremonies require the approval of the Chantry, and are officiated by one of the Chantry priests. In a community where there is mostly little cause for celebration, a wedding is a tremendous affair, and the whole district will turn out to enjoy the feasting and dancing.
Dwarves of Orzammar
The dwarves of Orzammar are noted for their polyamory (the keeping of multiple intimate partners), especially among the upper classes. While a dwarf has only one legal spouse, many nobles keep concubines, who are considered part of the household and have their names recorded in the Memories. A dwarf’s caste is determined by that of their same-sex parent, so many commoners offer themselves to nobles as sexual partners in the hopes of producing a child of the noble’s gender. As dwarven fertility is in dangerous decline, any noble child is considered a blessing, and such offers are rarely turned down. If such a union produces a child of the commoner's gender, however, the infant will be disposed of, as it would be part of the lower caste and an embarrassment to the noble parent's house.
Grey Wardens
Although Grey Wardens are not forbidden from marrying, it is rare for them to do so. Their short lifespans make them poor candidates for parenthood or long-term relationships. Even if they are not killed in battle against the Darkspawn, they rarely survive past middle age due to the Darkspawn taint. Most Grey Wardens dedicate their brief lives to fulfilling their duty, leaving them little time for pursuits such as family life. Furthermore, the taint makes conceiving a child very difficult (nearly impossible if both partners are Grey Wardens).
Mages
Mages, because of their outsider status, are not bound to traditional social mores and consequently enjoy greater sexual freedom than most. They are discouraged from marrying and reproducing, as the offspring of mages are very likely to possess magical ability themselves. Dialogue between Wynne and Alistair hints at some form of birth control or abortion being readily available to mages, perhaps to discourage the propagation of magically gifted children. If a mage does produce a child, it is taken from the parents at birth and raised under the supervision of the Chantry. Those children who prove to have magical ability are immediately transferred to the Circle, where they are held in complete isolation and taught to control their powers. Mages who do not wish to be separated from their children will sometimes conceal them from the Chantry and either train the child themselves or hire an apostate as a tutor (as with Connor and Isolde).
Orlais
Aristocrats in Orlais are notorious for their hedonism and extravagance, and sexual relations with multiple partners of either sex are not uncommon. The peasantry is much less tolerant of such behavior, at least in public. According to The Stolen Throne, the Emperor Florian reputedly had an affair with his cousin Meghren, which resulted in Meghren being banished from Orlais to Ferelden. The scandal surrounding their relationship was likely due to their being related, however, not to the fact that they were both men.
Qunari
Qunari don't have "family units". They don't marry or choose partners. Qunari do not even know to whom they are related. A Qunari's "family" are his or her coworkers.
They also don't generally associate mating with love. They feel love. They have friends. They form emotional bonds with one another. They just don't sleep with each other to express it. And if they do, they get re-educated by the Ben-Hassrath. If such a thing occurred and produced a child, the same thing would happen to the offspring as happens to all other Qunari offspring: It would be raised by the Tamassrans, evaluated, and assigned a job. Qunari don't waste people unnecessarily.
Whether same-sex attractions are frowned upon or otherwise by the qunari is currently unknown.
Homosexuality
Same-sex relations are generally considered odd but not immoral in Ferelden. Orlesians regard homosexuality as a mere quirk of character, and the Antivan Crows show a winking tolerance for (if not encouragement of) relations with multiple partners of either sex. There is pressure in certain circles, such as the City Elves and the human nobility, to marry an opposite-gendered partner, but this is motivated by pragmatism rather than morality; a homosexual couple cannot have biological children. For a dying race like the elves, it is vital that every fertile individual produce offspring.
Interspecies
Interspecies relationships are possible in some circumstances but frequently frowned on by one or both of the parents' cultures. Elves, for example, are bound only to produce children with their own kind, because the offspring of an elf and a human will always be human, which bears elven traits. Relationships with humans are considered traitorous and any elf who conceives a child by a human risks expulsion from his or her community.
Dwarves and humans can also reproduce (such a union will produce a half-dwarf), but this is very rare, as dwarves consider humans and elves to be lesser races.
Prostitution
Brothels are legal in Ferelden and in the Dwarven city of Orzammar. Although they are not considered respectable institutions, it is no more taboo to visit them than a seedy tavern or gambling house.
See Also
Resources
David Gaider[dead link]