From my experience, what you have heard is completely true.
Fortunately, I am past the age of marriage or children. So I no longer have to worry about all that stuff. But the way divorce/sexual harassment laws are today, hooking up has become a contractual financial issue as much as it is an emotional/procreation issue. And the more successful you are, the more dangerous it is. I know lots of guys who have been all but wiped out by divorce.
When someone tells me they are getting married, of course I say the polite stuff. But, on the side I try to warn them that there are a lot of dangers in that. I'm not saying don't do it. I am only saying that you need to be very careful. It is not something that you do lightly. It is a formal 'legal' transaction, and there are many pitfalls.
There are thousands of lawyers out there just waiting for a marriage to go bad, and then to take, or try to take, everything you own even if the marriage only lasts a couple of years. Even if you owned it on your own, before the marriage ever happened.