This man does not deserve this wonderful woman.
One of my closest friends went through almost the same thing as you Choc., she helped pay for his qualifications by sacrificing her own career and as soon as he was qualified, he came home, made love to her, rolled over in bed and told her he loathed the ground she walked on, had felt this way for as long as he could remember and told her he was divorcing her and taking everything away from her including her children.
He succeeded only in ruining his own life, he managed to take nothing away from her ... and her children wanted nothing to do with him as they stayed loyal to their Mum.
She too wanted to die and I recall her saying the exact same words as you ... and everyone understands that. Your words are a natural reaction and a very necessary part of you coming to terms with such a massive, unexpected shock. It is your own personal reaction (as it was with my friend), but you must not despair.
You must call on your hidden reserves to help you deal with this terrible shock. You must believe in yourself. You have done nothing wrong.
NOONE HAS THE RIGHT TO MAKE YOU FEEL THIS WAY.
This is your life and you will be able to live it. He will not stop you. Let him ruin his own life but do not let him ruin yours.
I recommend calling on everyone you know and telling them what is happening in your life. No matter how difficult it may seem and no matter how much you break down when you share this experience. It is so important not to have to deal with this alone as it's just simply too much. Not all your friends and relatives will know how to help you, but if you tell them all, you will find at least one who will help you get through this.
Please don't be alone. Even the strongest of us needs help from time to time.
Sending you oceans of love, hope, strength and hugs.
Let the son-of-a-**** go, he does not deserve you.