It sounds like you are in a very low place and there can be many reasons how we get into them.
I have been and what you write resonates so much with how I have felt.
I am currently in a much better place and hope you start making the steps soon that gets you back to yours.
But try to remember that however dark things seem, it can, and will improve, and even if you keep talking on MN for a while and getting the things out of your head, that is a key step to helping your self.
It is possible that everything has bubbled up and become raw again, maybe because, naturally, we repress these things and sometimes the time comes where we have to deal with them. And that is painful.
It is like grieving, and there are stages to healing and the process of going through them can be tough but what brings us out of the other side.
FWIW, you come across as lovely, warm, considerate and someone who very much deserves the love of a lovely man like your DH.
I know how hard it is to see the other side of where you are now, but it is there and I wish you all the best in getting there x