That's a question with a very long answer, I'll try to be brief. I believe the "collapse" started when Rome changed the rites surrounding the Sacraments. People had been led along believing that the Church never changes and then almost overnight everything was changed. Then (and this is where I put on my tin foil hat) homosexuals infiltrated the clergy in massive numbers and basically just destroyed everything from within.
It's a lot more complex than just that, but I think those two things contributed more than anything else. There was also the birth control kerfuffle, the people who were happy with the changes expected (and were led to expect) that the Church would change its teaching on birth control as well. There was a backlash when that didn't happen.
I see Satan at work in a feverish way right now. I believe he knows his time is limited.
We are having marriage being redefined right in front of our eyes into something that is not in accordance with God's definition of marriage. As the family is impacted so is the church.
The rise of feminism with women pastors is impacting the church as well. If you're not going to be faithful to the requirements of the office as noted in 1 Timothy and Titus, why will you be faithful in the rest of the word?
The Bible does note there will be a falling away in the End Times. But I also believe God is One who is not willing that any should perish....but He does have a time line.
I think He may be watching the church to see what the Bride will do. Will she get herself ready for the groom?
Will there be revival among His people?
As men, we are to be the spiritual head of the household. Are we preparing our families? Are we leading our families as we should?
I pray we, I, am not found wanting.
That's a perception that I had not considered before. I'll have to mull this over for awhile!
This may surprise some Catholics, but the homosexual "problem" within the clergy of the Catholic church was not a new thing. Reading the writings of men like St. Peter Damian demonstrate that this has been happening for centuries. Here are a few links about that: