Being a wife who is going through having a depressed spouse who, after almost 10 years, decides to sit down the day after Christmas and announce “I want a divorce” and “I love you but I’m not in love with you anymore”.
I have to first offer a heartfelt and emotional hug as I know I have needed one since I have heard those words.
Secondly I don’t have the exact answer to what is or is not right with all of the advice I have seen (I have read you thread thoroughly). I firmly believe that as long as there is love there is something worth fighting for. The question is what is it your fighting. What I seem to see most in your writing is that your fighting two major things. A) is your need of assurances and reciprocation towards your actions. It’s only a personal observation and opinion (one I have to constantly remind myself of when I start feeling my doubts) but as long as you are still in love with this woman will it not be enough to be able to have the ability to share that love with her? I know it’s human nature to WANT to be loved in return and you miss the love you were receiving before.
If you really take a moment the two outcomes you have are loving her and sharing/showing her this love with her there or loving her and mourning the woman/relationship that has left your life. It’s a struggle one I have daily and it gets overwhelming sometimes but the second option is much more painful then the first.
B) Your depression… it’s perfectly understandable to have some and feel the doubts while under this kind of pressure and I commend your getting the help. I also agree a bit with Anita you need to have a balance. You can’t base your center around your wife, it’s very much the mistake I made with my husband, you have to have your own center be your own anchor so to speak.
Now I’m not negating your marriage, it’s a bond no one should enter lightly and anything short of direct physical or emotional abuses or the absence of any emotional attachment (at which time the two should have no issues dissolving amicably) marriage is hard work made much harder by the standards of humanity today.

My story is a bit more complex my husband has severe anxiety,depression,and panic from military service and has had a depressive psychosis episode brought on by not taking his depression medication.
It has caused him to hallucinate and have delusions for the past 10 months. His delusions have been of me telling him I don’t want to be in the marriage anymore, that I don’t believe in us anymore. That our daughters doesn’t want him and will never accept him.
10 months of this and I have to take part of the blame as I did not know anything was going on. I was very focused on work,our teenage children,our disabled son, our home and other issues and I neglected to notice what was right in front of me. I can’t change that it has happened but I can change the things in myself to look ahead. We are going to counseling and are going to try and put the broken pieces back together. Am I depressed, yes I am. I had a wonderful life my husband before this break was attentive, kind, loving, a wonderful father and everything I could have asked for in a partner and I miss him everyday. I would be lieing, to myself and to you, if I said I wasn’t depressed in my present situation but I HAVE TO and you have to find a way to harness those doubts and negative emotions and use that energy to make a positive impact on yourself and your family’s lives. Why because you love them and you need to be healthy for them because if your not than anything you do with that energy will carry a negative effect.
I firmly believe in love and I hold hope securely in my heart. I pray the same for you.