OP, of course you are allowed to rant. Ignore the bitchy posts that don't add anything.
First thing, of course you are allowed to admit to being knackered! In fact I encourage you to be open and admit you're knackered. It will be a reality check for you and everyone else. why are you trying to protect your dh from the realities of life? Is he knackered too? If not, why not?
Then you need to change your mindset and get selfish about your time with your dc. See everything you do as either helping you spend quality time with your dc or taking away from time with your dc. The latter is to be nipped in the bud the former is to be encouraged.
You need to be organised at home and if possible buy in help. Now is not the time to be precious about getting help, or lack of privacy. My cleaner comes in twice a week, gardener once a week, window cleaner fortnightly and handyman monthly. It means we don't spend time doing "chores" but spend it with the kids. You should also think about an au pair/mothers help or a housekeep or a nanny (which is what we have). Again, just takes the "chores" away from running a house and means your time with your dcs is maximised, especially at weekends.
At work, you need to set boundaries and be more selfish. After I had dc1, I gave my PA strict instructions that all internal meetings were to last no more than 30 mins. Its amazing how much more efficient people are when they know they have got 30 mins to get stuff done. Also don't allow people to upward delegate and stop holding people's hands through everything. Believe me you will free up more time. Be really efficient in your diary. I am pretty much permanently back to back but it means that my juniors have raised their game because if they bring in something half arsed to see me, I am not going to sign off and they don't know when they will get in my diary next (the reality is there is always lee-way but they don't know this). Finally make use of technology. Don't go into the office at 5.30am, do stuff from home then do your morning school run (if that's what you do) and work in the evenings when the kids have gone to bed.
The food thing? Batch cooking is your friend for the weekdays, eat out maybe once during the weekend (nothing fancy) and if you "buy-in" help they can cook for the kids.
The other partners wanting to nibble at your profit share. Yup, that's normal. Ignore it. Remember your worth. Why do they need you? If you carry those two/three usps about you in your head, its very easy to remember that they need you and not to panic that if you show any signs of weakness you're a gonner, as I bet that's not true at all. Good luck, hope this helps!