If after requesting a change in the way people speak to each other in the house, your husband is still not speaking to you respectfully, you will have to explain to him exactly how you feel. Do this only when he is calm and in a relatively good mood. Make an effort to use “I feel” messages. For example, instead of saying “You need to stop talking to me disrespectfully,” say “I feel badly when you are angry at me and speak to me in an angry and disrespectful way.” Explain to your husband that you know he is going through a hard time and that you want to be there for him. Tell him how much you love and respect him, and encourage him to do something that would improve his self-esteem, e.g., learn, take a subject course he finds interesting, work out at a gym.
If he does not want to do something right now, simply be supportive of him. However, you need to be firm when explaining to him that you feel very upset when he speaks disrespectfully to you and that despite understanding that he is upset, it is not fair that you are the brunt of his anger. You can also expound on your very insightful thoughts about how the children may be emulating his disrespectful speech.
Hopefully, he will hear you – and life will get a lot calmer. Hatzlachah!