I can't relate to your boyfriend on any PCS level. I had and still on occasion have physical symptoms. The symptoms that you describe are things I have experienced just being a human.

The red flag is the depression. Seems to me that your bf has alot going for him good girlfriend, good support system yet he is dealing with depression. If thats the case its possible he is indeed dealing with PCS.

I suggest having him see a doctor to treat his depression.