Welcome to NT, CeCe!
I am so sorry for your troubles. JJ is so lucky to have a great soul like you looking out for him.
It is shocking how casually doctors treat concussion. They tell you that you're fine, even though they know darn well that CT and standard MRI are pretty much useless in diagnosing brain injury. Among the things, JJ really needs is neuropsychological testing. You both also need professional help for the depression.
I'm a Canadian, so I can't help you with navigating your the VA, etc... However, there are folks here with experience in that area and I'm sure they'll chime in with good advice.
I would, however, suggest that you contact the Brain Injury Association of America
www.biausa.org
There are local chapters all over the USA that will be able to help you access care, learn about brain injury and find support groups.
You should also consider contacting your local social services. Programs like foodstamps were started to help deserving folks like you. The medical situation is stressful enough without having it exasperated by financial worries.
Please reach out - you can't do this all on your own.
Bless You and thank JJ for his service.