Er, my ds2 made his packed lunch from about age 8! I hear you on the school run stress though, I used to be late for school every morning until ds2 started going by himself...I also hear you on the self-pitying and feelings of abandonment too, such an ugly feeling.
It's ok to talk about having a hard morning with the kids with your H, after all he is the dad and therefore should probably be kept in the loop especially if he's seeing them later. Maybe if you tell him what you need when you complain about them then he might not feel the need to go into Fixit mode? Like 'I have had a horrible morning and feel upset about it but I just want to complain and have you listen'. Or do it via text, with a few emojis or something. I don't know, what would be a 180 for you on this?