Hi,
I hope my opinion doesn't hurt your feelings. I really don't mean it to. I agree with the others that said it sounds like it's time to go on inactive status, at least for a while.
It sounds to me like you already know that in your head but your heart is telling you otherwise. Here's my take on it. If your kids are being upset by foster kids coming and going your family unit is upset. The biggest thing stressed in our MAPP classes were to take care of your family too.
When we began doing foster care I promised myself that when I began to question why I was doing this I'd stop. You have had A LOT of kids in a relatively short period of time. I would highly recommend you taking a break for a while and see how it goes with your children. You never know, they may ask you to foster again.
Best of luck. I am sure this is a heart breaking decision you are facing.
Michelle

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There are no unwanted children; just unfound families!
Biological Mom to 2 wonderful sons
Adoptive Mom to 2 awesome little ones
Foster Mom to 2 wonderful kids