Twin dad here. The struggle is real! This is just my 2c, but kids are designed to take and take until there's nothing left of you. It's not their fault, but that's just how it is. You can still be an engaged parent and have wonderful experiences with them, but you (major emphasis) cannot let your health suffer.

Keeping your mental sanity is as important as not letting them wander into a busy street or play with fire, etc. You are no good to them as an empty, stressed, beat down carcass of your former self. I have all kinds of strategies that I put into play when I find myself tapped out, but n=1 and I doubt it would be useful to others, I just wanted to share that I 100% get you. Take care of yourself, just like you would your kids.