If you feel going to the C for a one-shot session would benefit you, I'm sure it would help.
Your W makes me think of my H refusing to actually deal with his problems when he would say "I've never talked about that stuff!" What he was trying to do was avoid talking about it because he was uncomfortable with it...but when he would say that it came across as "I've never talked about that stuff, never have...and damned well never will!!!!"
I had to call him on the carpet with this to get him to see what he was doing. I told him...I know those aren't the words that are coming out of your mouth....but you say "I've never talked about that stuff!!" so emphatically that it sounds like that.
Out of curiosity...back when your W stopped going to a C did you tell her that no one will be able to help her if she's unwilling to talk about those things that need to be talked about? I know you don't like confrontation, but I had to do this with my H too...."honey it's often those things that you find most uncomfortable to talk about and don't want to talk about that are the key to the problem." He's quoted me saying that several times....it's apparantly stuck in his mind. You might try something like that with your W...I don't know, just throwing stuff out there for you to see what might stick