If these ancient societies deemed it helpful to their society then why wasn't it universally known and practiced?  Where is your evidence it was practiced? How about modern day China, Africa, and Middle East? same sex marriage there too?  

Bisexuality is its own separate orientation, not some sort of transitional state between straight and gay. Bi people are naturally bi, it's who they are.

no, gayness can't spread, the overwhelming majority of mankind (85+%) always will be heterosexual and there is absolutely zero reason for "fear"- the only thing openly gay people can do is help others accept their true self aswell instead of living a lie and hating themselves/life

as for marriage, do you think a union between consenting same sex adults is more damaging to it than large scale forced unions (not seldomly between minors)that have happened for centuries?

Marriage is a declaration of monogamy. "The word monogamy comes from the Greek μονός, monos which means one or alone, and γάμος, gamos which means marriage."

And monogamy has been the norm in most cultures for 5000 - 10000 years: http://en.wikipedia.org/wiki/Monogamy

Who cares I'm not religious the fact remains that the concept of marrigiage pre dates Christianiy and most other currenty religions by a long time.

Ancient Egypt, http://en.wikipedia.org/wiki/Homosexuality_in_ancient_Egypt.

What kind of logic is that? Because one country does it doesn't mean they all do it? Ancient greeks were very pro gay aswell.

I do know polygamy was commonly practiced but haven't seen same sex "marriage" in history books

http://www.randomhistory.com/history-of-gay-marriage.html and http://digitalcommons.law.yale.edu/cgi/viewcontent.cgi?article=2503&context=fss_papers It was still a rare occurence.

I can't tell you if the ancient cultures deemed it helpful to their society, but one thing is clear - once Christianity and Islam came into the picture, their arrival was detrimental to homosexuality. Pre-Christian cultures like Rome and Greece may not have formally recognized same-sex marriage (though they tolerated informal unions), but at least it wasn't frowned upon.

I myself do not care if a man loves a man or if a woman loves a woman. It's none of my concern if two people of the same sex love eachother and consent to being together. I'm not really interested in controlling other people's lives. There's absolutely no harm done.

Now that all of your points have been shown to be incorrect, any other reasons as to why you think Christianity has fallen? Other than people now having access to more information?

Despite the shaky ground that the OP was created on, the thread did have a very specific question:

"What do you think? Is Christianity "officially" dead in the West? What will happen with all the muslim immigrants in Europe? Will they integrate into society and become feminists and support abortions and gay rights?"

This thread was NOT a battleground for people to start posting their general thoughts about religion, homosexuality, and abortion rights. The amount of users who actually tried to answer the OP are slim to none, and to be quite frank I don't think its worth the effort to try veering the topic back on course at this point, as the thread has gone quite far from the original point of the OP.

Locking this thread and moderating those in need of it