Shelly I think you need to approach this as if they were not an essential part of your day to day life.
What I mean is: My parents live at the other end of the country, there is no one to 'help' other than who lives with us (me and DH) and we make our decisions based on that.
You HAVE to approach this as if they did not exist, because only then can they exist as 'grandparents' and not a solution to childcare problems.
You DO have a choice. It may not be one you like, but if you want their help you give a little control to them. So live like you're on your own with your DH in the world.
Its scary but my goodness, although it may save you money, the relief from the stress is priceless.
If you had no parents, how would you cope? Answer THAT question, and you'll have your solution.
My folks are thankfully, lovely. But they are neither use not ornament as far as our day to day life is concerned. They are loved by my children (and me) but have no input. DH and I sort ourselves out. Its tough. We are happy.
The balance between what you think you need and the stress you're experiencing is completely out of whack.
Good luck.