SoH, I think different personality types deal with things in different ways. I had what sounds like a very similar experience to yours - I had a 42 hour labour, with 4 hours of pushing before an emCS. My daughter had her ear presenting. You are the first other person I have come across who had the same thing. My daughter was well and truly jammed after the length of time I had been in labour - I had no pain relief except g&a plus meditation, and a TENS machine for a little while. I am proud of my labour - friends and my sister have said they were all demanding epidurals after just a few hours. Since reading your first post tonight I have looked up asynclitic, as I had not heard the term before, but it was was my daughter was too. The Spinning Babies website says that these labours are often far more painful with much stronger contractions, and last for much longer than normal labours. They frequently end in caesarean.
I am angry to this day about the things that went wrong with my daughters birth. Many mistakes were made by the hospital, and many things could have been different. Among many indignities 2 things stand out in my mind - my spinal block wearing off and wondering when they were going to stitch me up (they had had to call a more experienced surgeon from home, hence my being left open on the table with the spinal getting weaker,) and the nurses later using a cable tie to attach my catheter tube to the bed so I did not get up to visit my daughter in SCBU. I believe that no matter how difficult a birth is, this kind of thing should not happen.
However, I have managed to focus on my pride in my long and intervention-free labour up to that point, the fact that once she was born (and against the odds, since she was in SCBU and I was in HDU and kept apart for 3 days) I managed to breastfeed her till she was 10 months old, the fact that she is beautiful and clever and strong. These are all things that are down to ME. I am pregnant again, and am much more cautious this time, but also much more optimistic too.
Please go and see someone. It IS possible to feel better about this. And don't shut up about it. Obviously pick your moments (I have a very nice job where I get to stay away overnight and have a drink and a natter with colleagues, and often find someone who wants to know,) and then tell people just how hard it was and how WELL you did! You are not a failure - once you would have been dead, but you and your child are alive and well and you managed all of that.