My question is why does he believe you will not be able to look after yourselves “soon?” I see that he has hereditary disease in his family, but unless either of you have a serious illness now, you should be able to hopefully take care of yourselves for many years to come. If he is worrying about things that may not even happen or may not happen for a long time, I would probably remind him to be mindful of his life as it is right now, that everything is okay in this moment and that if things pop up in the future, you will be able to deal with them then. Of course, it never hurts to have a financial plan like putting some money away each week just in case you need help in the future, and developing some sort of plan may help to ease his worries, but worrying to an excessive degree when everything is really fine in the moment can actually bring on health issues and can become a self-fulfilling prophecy on its own because of the stress it causes.

If he continues to worry even after coming up with a feasible plan, I would see if he would consider counseling.