When it comes to family law, there is a lot to know. It is a complex process that involves a lot of things. Every state varies according to the laws that they have with regarding laws within the family arena. Some of them have certain requirements as to what is required in relation to marriage, as well as many other things.
Since there is so much to family law, we will concentrate more on the wedding aspects rather than two people who are marred and living together. For the most part, it is good to note that two people unmarried and living together do not have the same protection as those who are married. Engagement runs along the same along the same lines and does not mean anything more than a promise to marry. For that reason, when two people get engaged a woman is not supposed to keep the ring if they break up.
When two people get engaged and then break up, the woman has no right to the ring, since it is only a promise to marry and nothing more. In some states however, if the person who gives the ring breaks off the engagement then the other person can keep the ring, but that really depends on the state. Other gifts however, both parties can keep since it is just like friends giving gifts to one another.
Other things that are beneficial are government, employment, estate, medical, and death benefits. Additionally, there are discounts, housing, and family benefits.
Some of the states require blood tests, residency, along with many other things. Some of the states will allow two people to marry right after gaining a marriage license and everyone differs in regards to how long they are valid for.
In some cases, there are marriages found invalid after so many years. This tends to happen when one of the people in the marriage do not reveal another marriage before going into a new one. There are other reasons due to age and other things as such that could render a marriage invalid, but there are some protections for the other persons in many of the states.
Every state varies as to the family laws that they have, so the best thing to do is check with the state that you live in.