Dana
I hope the next couple of days will go OK. I was in hospital when I had my post C-section infection. So I can't quite believe your dh has gone off and left you to it!
"I think partly this is my fault as I didn't ask DP to stay" No, it is not your fault, I would hope most people would realise post surgery and an infection you should not be left alone in charge of a potted plant, let alone a baby!
"I should have but I didn't want to put him in a difficult position." I really think you and dh need to discuss what is expected and be prepared to speak up in future.
"I guess part of me was just hoping that he would come to his senses and make other arrangements." So now you know he is not very observant or just doesn't think things through, or does not care much. I sincerely hope it is one of the first two and he will be able to work on this.
"He's travelling to a work event which has been scheduled for a while - my original due date was 27 August so he didn't think he'd be able to go but when LO arrived early he decided he would."
he decided he would? Did he ask you what you thought? Did you not at any point say or point out how abnormal disheartening off overnight when your wife has just had a baby is? Please do be honest with him.
"I'm disappointed in that decision but he'd have to have left us sooner or later and the next few days will help me gain confidence that I can cope." Coping when well and coping when recovering from major surgery and an infection are two different hings.
You are now a mum and need to put your and your baby above other things, IMHO.
"It's funny - I'm so used to being strong and capable in life " I think you are still strong, having had an infection like this, it was incredibly hard.
" I've realised I need to be kind to myself whilst I'm recovering and not put myself under pressure to be superwoman!" Absolutely you have already made a human being, you are already superwoman.