Feeling alone with my mental health issues.

Hello, I am kinda new to this online chat thing. Well at least for chatting about emotions. I'm not good at talking about these sorts of things. Lately I have felt very... worn down by everything. I struggle with severe Anxiety and depression. Some days I have this more under control and other days I don't and I find myself in this weird mental fog. While in this fog I almost feel nothing, I don't remember a lot or what is said by my wife. Which from time to time can cause arguments. These arguments can sometimes cause us both to stay up late and lose sleep which makes things worse. I feel like my wife doesn't understand what it's like living with Anxiety and depression and just thinks I'm making excuses. I'm really at a loss here as to what to do.. and how to cope. I just wish she knew that I don't do these things on purpose..