Hi OP, I just wanted to say I have been there too though a while ago (see my temp name). Nothing like as traumatic, but also bitter disappointment in missing the "full natural experience", fear that i had damaged my relationship with my ds, the lot.
In fact I wrote an article about it afterwards, and was able to interview two close friends who had also geared themselves up for a full-on orgasmic natural birth experience. I still feel quite cross - NOT about the birth interventions, which saved a lot of lives mine and ds' included, but the whole romantic hoo-ha that we'd all fallen for - and, crucially, taken personal responibility for in that modern, individualistic way - when of course none of us has the power which is essential if you are going to take responsibility. We ca't control any individual birth, even our own (well our dcs but yswim). We can only act collectively in this. Our responsibility is to speak out and that is what you are doing - speak out so other women can be more emotionally prepared for physically traumatic births, and those births are handled better so they don't end up emotionally traumatic too.
After I wrote my article I had a very nice and thoughtful letter from no less than Sheila Kitzinger herself. I can't remember the exact words but I felt I had given her pause for thought. Not about the fact that obstetrics should put women at the heart of the process, but about the way her message was leaving women like me and my friend s feeling when nature had other plans. As pp have said, dying in childbirth is, sadly, extremely natural.
I wonder whether it was after that that she wrote her book on birth trauma?
OP YOU HAVE NOT FAILED. Thats like berating a river for failing to flow uphill. However, your other responsibility, as well as speaking out, is to seek rl help as your thoughts are the trauma speaking and the right support can I hope get you to a much bettrr place, as it has previous posters.
For me, writing the article was a part of the help I needed, that and the wonderful relationship I had with my adorable ds then, and still do 18 years on! But I don't think I was as hard hit as you clearly are, so please do get help. 
