Want to leave but what about abandonment laws?

In this case, one spouse wants to leave the marriage and has communicated multiple times after marriage counseling that they want to separate and why. The other spouse refuses to accept this news and insists that they can and should work it out. There are 3 children from the marriage.

The unhappy spouse is worried that the other spouse can claim abandonment if they establish a residence elsewhere.

What can be done to begin the separation stage so this person can end their unhappy marriage? Are there steps that one can take to leave but protect themselves as well?

The abandonment issue is really no more than a threat these days. In order to move forward with the process of separation and divorce one spouse must move out. If the spouse who leaves is the breadwinner I would say that it is a good idea to ensure the dependant spouse has the money to ensure his or her basic needs (and the needs of the children) are taken care of.