I would like to help you with your question.
I understand what you are saying...you want to be free to raise your son without the examining eye of your parents. That is exactly what needs to happen. Your son deserves - and needs - to be raised in the way that you and your husband deem best. I can see how your parents came to take responsibility for his upbringing while you lived with them...but those days are over. And...he really needs his grandparents to be his grandparents! Meaning that they can spoil, love, and be actively involved in his life...but major decisions in his life need to be decided and managed by his parents.
How about this...since your parents have had such an important role in your son's life might you and your husband be willing to give them a gift in appreciation for their love and support. Perhaps it could be a special portrait of your son and put in a frame with an engraved plate that says, "Thank you Grandma and Grandpa for all you've done". Or, perhaps it is some other gift that would convey that same message...that you are appreciative of the role they have played.
My point is to acknowledge that PAST role. And then when giving them the gift you would say, "Mom and Dad, I don't know how I could have raised this child without your love, support, and graciousness. Now that we are married, we will take over from here." You see my point here?
Your parents need a way to transition away from co-parenting with you (because that's what they did) to know being grandparents without the necessity to be involved in anything other than grandparenting.
Also, I want to encourage you to get the following book:
Parenting with Love and Logic by Foster Cline and Jim Fay
This is the very best parenting book that I know of. It is easy to use, parent-friendly, and very effective. It will help empower you to be the very best parent you can be.
I hope this answers your question. If you would like to chat, let me know.
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