What you are feeling is being combined into one great big ball of unhappiness.
I could be wrong, but I sense that you are just as dismayed with your commute situation as your are with your M. Don't combine them or make one the scapegoat for the other.
Like I said I could be wrong, but it seems like that 500 miles commute is burning you out, taking time away from what recharges you. You spend a lot of time working hard to have a good life, but you end up with no time to enjoy the fruits of that labor. Further you see your W enjoying the benefit of that work without contributing in the same way you do.
New job closer to home ? Telecommuting ? While your W does not want to move, if it comes to that, that can be a deal breaker of it's own. KWIM ? Remorse would not hesitate. Selfish people would and do though.
I get it. I am tethered to my job and contribute the majority of my family. While my W income helps, she got to pick a job that doesn't pay all that well, but is "rewarding," and gives her some time to do as she pleases.
When you don't get credit for that and know it is appreciated it makes you wonder why your are making these sacrifices. You are working yourself to an early grave to make the woman who cheated on you happy ? I get why you are where you are. I would feel the same way.
Prior to Dday I did 90% of the household work. I am surprised I did not burn out or end up leaving my M. I was co-dependent and wanted my kids to grow up in a two parents household without the things I did. I was trying to fix my past by bringing that pain into my present. This was killing me and draining me of any joy in my life. People need joy too.
So I think you need to tell your W that things have to change or we are going to get a D. Things are too comfortable for her in every aspect (including, the false R). She has to contribute too. It is what a healthy M is. Not this you work your butt off to support her while she benefits from this arrangement.
Part of my new M was asking for things to make it a lot more equitable in a M. Housework 50-50. If I ever get a chance at a great opportunity that pays less, we need to consider that my W would have to get a different job, we would move, etc. I am not saying we would just do it. We would decide it together. Nobody gets a veto.
All aspects of the M need to be shared equally.
I do not think it is unreasonable to tell your W that you have to change "something." 'Cause current state is not working for you. The commute is killing you. How cruel and selfish is it if she simply refuses to do anything to help the situation ? Ask her for ideas to make this easier on you.
Tell her you are already living like you are D. You don't want that, but she is not making any attempts to work towards anything else. So your only option is to just suffer ? It is your life and you have the only say in how your are going to live it. If she isn't going to come along she can be left behind.
You don't want that, but you don't see a reason not to. Her A made the D the default path. Refusing to help you heal and forcing you to keep the job you have, without consideration for what it is doing to you shows that she just doesn't care or love you. Living in a loveless M with a draining soul crushing job. What do you have to lose ? That yoke around your neck ?
She is benefiting from your pain. Tell her that. Force her to confront this. Do the opposite of the 180 and make it present always. Remind her that she brought you here. Expect and demand the respect you are due. If she doesn't I think you have an answer on your D question.