How can i get my husband to care more for my disabled child when he is stressed about the situation?

Mindfulness: There are many books on mindfulness and dealing with stress and anxiety.

Counseling: I recommend you and your husband enter couples counseling to address your concerns and better understand your husband's feelings.

Best I can suggest:: Reframe the question as: "how can my husband and i best care for each other and for our disabled child, and reduce the stress we are all under because of this situation?" - and i think the answers will come more easily then.