Changes after having Neuritis

I was diagnosed with viral meningitis a year ago. A few months later I started having severe headaches, which they diagnosed as Neuritis. It has been one challenge after another since then. My wife says I am a completely different person. I have severe back pain all of the time. I am in a state of constant depression, which is only made worse by anti-depressants. I even had an affair. It was like I was living a double life. I was happily married on one hand and seeing her on the other. I know, that doesn't sound like an effect of meningitis, but this is something I wouldn't do. I love my wife and my family - I've been married for 20+ years. I don't even remember most of it, it was like I was in a fog. I was not taking any medication at the time this took place. The doctors I am seeing keep treating the symptoms and not the problem. In the last few months I have had an MRI on both my head and my back. Head was fine, but the back one showed severe inflammation in the back.