The 'gay rights' movement, as it is called, is only one of many assaults on the moral fabric of society. When it comes to issues related to marriage and sexuality, the assault started long before homosexuality became popular in recent decades. It didn't start then, but in the 1960's, the idea of 'free love' was popular with some of the young people at the time, having sex with who you wanted to. Birth control pills had been invented, and the government soon legalized murdering babies in the womb to do away with the consequences of free sex.
There was also an increase in the divorce rate. That is an attack on the family, too. Many preachers pay little attention to Christ and the apostles' teachings on divorce. If church goers do not read for themselves, it is unlikely that they will know. Many preachers get divorced nowadays, too. The rates of people committing adultery are high, which contributes to the divorce rates. Metrics that indicate that fornication is prevalent among the youth, including teenage pregnancies, indicate that fornication is a problem in the churches. And a little leaven leavens the whole lump. Rarely do you hear of a church practicing church discipline for such sins as the Bible teaches.
We could also talk about various philosophies in society, such as the Feminist movement. Decades ago, this movement that that there was this bad thing called the patriarchy, that always kept women down, and women's problems were all the fault of the patriarchy. Certain aspects of patriarchy are Biblical, and Feminism has grown in power, influenced churches, and weakened society. It has disrupted marriages and homes, and many men have not grown up with male role models who taught them to bear the responsibility for the family.
Widespread acceptance of fornication in society has also led to a lot of one-parent homes. Some of the men fornicate and don't raise their own children.
In the midst of all this mess, those who practice homosexual perversion have positioned themselves as some kind of oppressed minority. In the past, minorities were identified by racial characteristics, or perhaps gender. But now, someone is identified as a minority based on what type of sexual things he likes to do in the bedroom. They created this concept of 'orientation' and sold the public on it. Just as the entertainment industry and the media has glorified fornication, it has gotten behind the cause of homosexuals and made homosexuals out to be victims of discrimination, and painted those who speak out against this type of perversion as bigots.
So yes, the homosexual agenda is a war on society and the family, but so was the free love movement and it's effects are still felt. So is the lax attitude in our society toward divorce, and the legal system set up to make divorce easy and to make it easy for children to be raised without much influence from their fathers. There are a lot of ways the family is being attacked. Homosexuality is one of the more shocking ways, but it is only one of many.