How does the gay and lesbian "problem" impact society?
Society impacts society. It is the perception of there being a gay and lesbian "problem" that is the problem.
The westernised society has certain "norms" by which it measures and judges others. This causes a problem because the world, or the "Global Village" as it is so quaintly put, is not all westernised and different ideals create misunderstandings that can cause war.
In the past, countries were more isolated, tourism was limited and interest in other cultures was not necessarily encouraged. This is why it was less of a problem or was a geographical problem depending on location.
Now that society has access to basically everything, well-meaning "Westerners" (particularly) visit culture-rich communities, share their own culture and learn enormous lessons about the culture of others. At the same time, they discover wealth that they are lacking in their own country and which they want to have a share of. There is nothing essentially wrong with that. Other cultures benefit enormously from the technology and processes that a westernised country can introduce them to and a mutually beneficial relationship develops - some of the time.
The cultural aspect has been mentioned here in order to link it to the gay and lesbian "problem." Westerners have set ideas. They do not like (and unfortunately this is a characterisation as it is certainly not true of all Westerners) norms that do not match their own. So other cultures are frowned upon - they must be wrong! - and are duly avoided. But when gay and lesbian people are in their midst, they do not know how to cope with this "problem" or how to avoid them.
Words themselves and concepts become so important that the essence is lost. A huge problem is the "marriage" issue. It doesn't seem to matter that heterosexual couples are rejecting traditional marriage for live-in arrangements, or treating marriage disrespectfully by marrying and divorcing repeatedly, but let a gay person suggest they want to "marry" and it becomes a travesty. Society causes its own problems due mostly to communication.
Even if one believes that gay and lesbian people may never be able to "marry" in the same sense of a bond between a man and a woman, they can have meaningful, ever-lasting relationships which they want to commit to paper. Is that a problem? They want to call it marriage. They want to swear before God. Why then not let God be the judge? Just as the gay man does not judge a person (or maybe he does) when this person divorces and stands before God AGAIN and swears a lifelong bond. People argue - and it's one of societies hottest debates - that gay and lesbian marriages are against God. Are they the same people who stand in Church and swear an everlasting bond to their second or third wife/ husband?
The basic problem is that essentially gay and lesbian people look the same as everyone else. Many of the people of a different religion or culture look a little different - they dress differently, their skin color is different or there are obvious characterisitcs that show their difference. Gay and lesbians look the same. How can a "normal" person avoid this sector of the community?
There's the problem: society.