Some can navigate their crisis while living at home...but the spouse needs to leave them alone as much as possible and allow them to take their journey. The spouse basically has to accept that their other half is now a roommate and not who they expect them to be. I have seen a couple of them stay at home the entire time IRL and they came out the other side. The spouse has to learn to accept from for who they are today and not who they were pre-crisis.
For some, leaving home, filing for divorce, is a necessary part of their journey. It all depends upon their childhood issues and what they need in order to heal themselves.
They are some who have a "mild" crisis and others, such as many of those we see here, are "really in serious crisis mode and act out completely.
It all depends upon the person, personality, coping skills and, of course the childhood issues.
Sit quietly, the answers will reveal themselves when you least expect them to. The past is gone, the present is a gift and you need to focus on today, allow the future to reveal itself when it is ready.
