How are gay people treated in society?

This question is extremely broad, so I'll just cover the main areas of history where homosexuality was accepted. The general rule of thumb is that male homosexuals were considered effeminate/against religion (especially if they preferred to be penetrated), and female homosexuals were ignored or presumed not to exist. This was not the case in the following eras:

1. Ancient Greece and ancient Rome. Greece had a rigid system of pederasty, in which an older man acted as a mentor to a younger one. The younger man must accept his sexual advances without encouraging them, and could thus escape from the whole gay=bad stigma. Once the eromenos, beloved, grew old enough to have a full beard (usually in his early-mid twenties), the romantic relationship should end and a very strong friendship should ensue.

Rome was more casual about it. As long as no freeborn male Roman was penetrated, they didn't really care. If the relationship continued on too long, however, it was a commonly accepted belief that the older partner wasn't actually pentrating his lover, but being penetrated, and he was scorned for that. Again, the growing-a-beard was a good marker. A man wasn't looked down on for having a long series of young male lovers.

2. Homosexual romances were accepted, even by the Christian Church, for parts of the 1100's and 1200's, and close, intimate relationships between men were celebrated.

3. In the Victorian era (late 1800's), London was home to a flourishing gay community, particularly in the theater. (In general, the theater was a good place to be gay. For a long time, men played all the female roles, so actors were more forgiving of genderbending.) If somebody kicked up a fuss, though, the authorities could and would arrest homosexuals--see Oscar Wilde.

4. In the 1920's, gay communities grew in London, New York, and Berlin. In the US, this was generally part of the Roaring Twenties culture, which flaunted traditional gender roles. There was a great backlash during the Great Depression.

5. Throughout the 30's and 40's, Berlin was basically a safe haven for LGBT folk. Homosexuality was technically illegal, but virtually no one enforced it. Drag clubs were popular, and many gay/lesbian couples lived openly until the Nazis took power. In the concentration camps, homosexual prisoners had the highest Death Rate of any group except the Jews. They were more likely to be raped or beaten, sometimes by their fellow prisoners, and many were made to carry out their sentences even after the camps were liberated.

6. In the 1950's, the gay rights movement (called the "homophile" movement) began to form underground in the US. Greenwhich Village was a very popular gay neighborhood from WWII on. The Daughters of Bilitis and the Mattachine Society were founded, and became the first gay rights organizations. During this time, however, many gay men and women were sent to psychotherapy for treatment, and homosexuality was still a disease.

7. The gay rights movement gained more power in the 1960's and 70's, after the Stonewall riots in the US.