I am so glad you understood that it was chizuk! I never doubted your love for them and I get the sleepless thing. My kids are awesome but lousy sleepers and I don’t think I slept through the night more than two or three consecutive days for 19 years. (Yes, I really do mean that)
I am sorry I can’t offer more without giving away all my trade secrets (No, I really do not mean that).
I went through a period like that and I worked hard to change my view because I felt like I was always frustrated at the wrong people and I knew they could sense it. It took work but brought me such tremendous menucha. It has been 20 years and I generally feel like the rest of life interferes with my time with my kids, as opposed to the other way around.
Here’s my own personal chizuk that I made up for myself. The reason it is sooo hard to be with your kids all day and feel useful is because it is such a TREMENDOUSLY HUGE mitzvah and tafkid that the yetzer horah works triple overtime to make you miserable. See, that’s how important you are, and that’s what you are up against! You are awesome, so kiss those pudgy cheeks and thank Gd it’s all temporary.