Sorry am I reading this right ?
Your husband works 6 days a week, sometimes not coming home until 8 at night, you have one child of eight, you have 'quite a bit of free time' and you still expect him to come home and ' put a load of washing on and make your daughters packed lunch '?
The fact that he 'does the dishwasher' , that's a bonus, but do you really expect him to 'do the housework' when he gets home at night and you've been at home all day?
You say that you are 'seeing more and more of the man I married', perhaps if your expectations of him weren't so skewed, ie 'how should housework be shared ?', he would see ' more of the woman he married' ! If you are not working it's simple.
You do the house etc and he brings home the money that 'allows' you to be at home all day ! No wonder he's getting frustrated and taking stuff out on you, ' I have got into the pattern of not discussing certain stuff in case he blows up', is that whilst he's 'dealing with the dishwasher when you have had 'quite a bit of free time'?
Have you for one minute considered how he might feel ? He's doing a really stressful job, the hours of which far surpass the recommended limit of hours for a work/life balance in order for you not to have to work.
And before you all start, with the usual , ' well he's lashing out at her ' and making her life a misery I would suggest to you all that you 'consider' the reasons above.