Big hugs Nicole. No advice but I am always here to listen :)
Nic, this could have been my post at the same stage of motherhood. I remember being sad that the baby stage, the toddler stage....that it was behind me. But every stage has some great things. You will adore and enjoy the boys they become as well as the young men whom you accompany on college tours. (and now I enjoy the college life of my daughters vicariously...lol!) Continue to seek God first and everything else will fall in place. That is His promise in Matthew 6:33.
Just want to add that the meltdown could have been my post as well!