The bad news
The purpose (at least the official purpose) of many institutions (and many books also) is to help people in their suffering. Some teachers take advantage of the peoples sufferings and others just keep some secrets because they don't want to loose the dependency of their "students" and they don't want them to become better teachers than they are - of course it took them a long time to reach that point.
So how to find the lasting happiness is mostly described in a heap of thousands of pages and hidden between thousands of teachers wise words which nobody can keep in mind.
The good news
The fundamentals you should keep in mind to end your suffering are not really difficult and you don't need to get a monk or to be member of any religion. You just need to finish riding your pain like a fool in the dark.