Losing a job is a really depressing and stressful situation for anyone.
Primarily, please don't remind him or throw it in his face that he lost his job, even in an argument. Try to make sure that you divert the topic of employment from the majority of communicating. You can also try to come up with things to do leisurely at the spare of the moment to distract him from thinking about looking for a job; the littlest things count. As for the actual job search process, he needs to make sure he applies for unemployment insurance in the state he resides in. While collecting that temporary income, he should be looking for work at least 2 times a week. In addition to that, he can either look into temporarily volunteering either for events/projects or a specific place once or twice a week. This can help to add to his resume and prevent an employment gap. Not saying he is going to be unemployed for a long time; however, it's unpredictable. In doing either, during a job interview, he can answer the "What are you doing at the moment/now?" question without saying "Nothing right now...". That question can determine from the employer either he is proactive while unemployed or just lazy/inactive.