I have been following your post, and so hope to help just a little bit. I have depression too, and know that the brain may shrink. But ya know what, I fill that space that may be hurting with other things. The brain has a remarkable ability to use other areas, that are not so effected. Stress about this will make you obsess. Heck as we all get older, the brain does its thing. I fill myself up with books, and that is no joke. I read obsessivly, and it takes my mind to a better place, some adventure, some new idea. I believe this makes up for any deficiency that presents. I am also bi-polar, I refuse to give into it, and seek the help when I need it. Try to change your thinking. By changing your thinking, you are going in a more positive direction. The more you think about negative stuff, the more you worry, and it gets to be a never ending cycle, that magnifies over and over again. This change of thinking is by no means easy. When you find yourself doing this, recognize it for what it is, and force yourself to think about some other subject, and how you might fill in what you believe may be missing. The brain is a really cool organ Matt. Neurons, can go all over the place, and re-route, bypass a trouble. Look at Abby who was shot in Arizona....Her brain is making up for the bullet that hurt hurt hurt her. That kind of determination will give her the recovery she needs and wants.
If you have a hobby, go back to it, try reading, try being social and join some activity. Even the YMCA has things to do, that most anyone can do. It is not expensive and meant for public use. Hit the library, release your worry. We all will be here for you. I get and need the same kinds of reassurance as you do. I run back to NT all the time for help. If I let myself think that my depression was shrinking my brain all the time, well I would just have a peanut left, and ready for some psych ward. I am better than that and so are you. Your brain is fine Matt, fill it with all the good stuff you can. It will improve your mood, and you will feel better about the whole thing. It will OK Matt, trust your brain a bit OK? ginnie