There are any number of well made or well written advice for any need that is published every year. One item will be marriage books for couples, something that will affect those who are going to have need of advice about marriage and its many concerns. There should be a lot of these too, and there are experts that are working this field.
This means you have many options here, and usually you could do some good research for the exact things you need through an internet search. You may have specific needs here, like subjected related to kids and raising a family. Some of the subject fields may be answered by specific specialists too, since these could be already a field of its own.
Marriage of course encompasses so many things that could be spread widely across fields and disciplines. One prevailing expertise is psychology, and sometimes this is a thing that is also specialized, especially when it comes to married couple concerns. There is a psychology for children, for mothers and for the relationship itself.
The field is broken down into certain classifications that apply. This will actually make your search easier, if you know precisely what you need. For advice before marrying, there will be a set of books that are available, and another set for your need of advice on how to make relationships last or make them work through certain problems.
Often, people seek some good ideas or concepts that come from authors who are recognized experts. It means that the things found inside a book may be generalized. For more specific needs, some could go to experts who might have clinics, but then simply studying could also lead to a method of self healing that applies.
This is not a recommended process for clinical concerns, but when the need is related only to a general lifestyle thing or even wellness concern, books often do. The folks who read them simply take out the concepts and perhaps make them relevant in their lives. It is not treatment at all, or even something approaching clinical therapy.
There may be those items that offer therapy, but this is something of a DIY that has been proven successful. Sometimes there are authors who may be relating their own experiences. This type of sharing is often accepted by publishers when the subject or the writing will typify a certain sector of the demographic.
Learning lessons through books is an age old process. And those who are educated know how to use this process to their benefit. Things do not reach extremes when reason and rational thought aided by the best ideas around are present in the minds of folks.
That means there is much use of books that offer an aid to better thinking. This is something that all publishers study and therefore you could at minimum rely on any book to address its topic with some relevance to you. For many this self help process could begin and end with one book.