Honestly, to me it also sounds like her depression is clouding her feelings about everything. Specifically, you mentioned she had a bad day at work and then ended up saying “I just can’t do this anymore”. Instead of that being related to a bad day with your relationship, her work seems to have triggered it.
She went off anti-depressants and therapy… was there a medical reason for it or did she just doesn’t want to do it anymore? Now she has changed her mind and is going back on them.
She told you she is struggling and that something is wrong with her. You said you could have been more available and interesting. It sounds like she might be looking for a way out of her depression and started thinking you were the source of it. And given what you wrote, to me it doesn’t seem like her relationship with you was any kind of cause of the depression. Although partners should keep doing things to maintain interest, it takes two people to do that. It isn’t the responsibility of just one of them.
I don’t think no contact is an answer for this. You were together for 12 years. That’s a long time. She said she is struggling.
I can’t really make a judgment on what specifically to do. I can tell you one story.
I had a friend who was very close to me commit suicide last year. He was suffering from depression, I had known him over 10 years and had no idea he suffered from depression at all. He had a family and 2 kids. It was a complete shock to many of the people who knew him but not all of them. Specifically, his immediate family knew he had been suffering from depression for some time but thought he was getting better. I’ve never really suffered from depression myself so I had no context to understand what he went through and still don’t. I just know it must have been pretty bad to make that final decision he made. His life was good, he had no issues other than his depression. It wasn’t like his life had fallen apart or something terrible had happened that triggered his issues.
Give what happened to my friend, I take hearing about depression very seriously. Your wife sounds like she is having problems, isn’t sure what to do to solve them and is trying different things to resolve her problems. I wouldn’t advise going no-contact at this time, I wouldn’t advise pushing her too much. Depression is an illness and she might be sick and need support.
My issue is: I don’t feel confident giving any advice except that I think going full on no-contact is not a good idea in this situation. Other than that, I would worry about any advice I might try to give.
I don’t understand what having depression to that degree is like and I don’t know what is best to help resolve it. I just know it can be extremely serious. I guess I could give one piece of advice and that would be to talk to her doctor or someone else who knows more about depression and what might be going on with her given your situation.