I'm glad you have come here, and that you have met Sophie_M and the others here. Their advice is pretty good. Your partner is lucky to have such a caring person. As mentioned specifically you too need care as you are going though a very worrying and stressful time.
Do you have anyone to support you? A family member or friend perhaps? The simply have to listen to you and show they care -that's all, but it can make a huge difference to not deal with all this in isolation.
You are of course doing everything right, and if it does not seem to work or be appreciated then it is hard not to take it personally.
Maybe you might consider a couple of ideas that might help you gain perspective and realise your very real worth.
The first is your partner is facing a whole heap of problems: financial issues, work and dealing with legal hassles with an ex partner. These are things that may not be easily resolved and may be things one has to live with for a long period.
The second is many people have the idea that they need to 'fix' things, and hopefully do so promptly. When that is not possible this can fill the mind, generate feelings of hopelessness and even make one so preoccupied as to lock others out (I know, I've been exactly there).
Under such circumstances please realize it is not you, nor probably even your husband, but adverse circumstances and their effect.
I guess the only thing you can do is continue as you are, promoting professional help, giving reassurance you are there for him, and at the same time trying to persuade him that there are other enjoyable interludes that can make life worth living despite all.
What do you think?