This is such a hard place to be:( I didn't have much support with my last three births but dh is able bodied and my children were older for the last birth. That helps a lot. There's not much I can add but really do wish to emphasize watching your body. I recover very quickly from birth aka wrestling with a car seat when my last one was three hours old...but I always over do it and my body does let me know.
And I also second starting the kids on chores they can handle now. My son used to be very unwilling but we eased him into it, and now at 12, he's awesome. I found it easier to deal with when I remember that it's often frustration as opposed to laziness. And I tried to find ways to make it interesting because frankly chores are BORING. I don't like doing them either LOL. So we try to do music, we talk, tell jokes etc. That helps. It also helps when I sit him down and explain to him why I need his help so much. I really feel like this is important in developing empathy. It doesn't always come naturally!