Whoa. Correct me if I am wrong, ok? That's a lot.
So if I understand it right the problems you have identified are:
You want to cohabitate.
- Hubby does not want to.
- Ben prob doesn't?.
- Grace -- on living together is...?
Grace wants more time with Hubby.
- You -- willing for that, also willing for time as a foursome to dinner.
- Hubby -- ?
- Ben -- ?
You want to rekindle things with Hubby now that you realize you were NRE drunk.
- Hubby -- willing? Not willing to rekindle?
- Grace -- supportive / not supportive of this?
- Ben -- supportive / not supportive of this?
Hubby wants to maintain separateness.
- You do/do not want to maintain separateness?
- Ben --- ?
- Grace --?
Hubby requested you unfriended Ben from facebook.
- You have/have not unfriended Ben on FB?
- Ben --- how's he feel about this?
- Grace -- how does FB policy changes with metas affect her?
Ben wants to see you more, feel less restricted, show you to his family and friends.
- You also want to be more "out" to people.
- Hubby -- ?
- Grace --?
Ben is afraid this polyship is ultimately doomed. For him to feel better he needs _______?
- You willing/not willing to meet the need. (cannot at this time, need is not known)
- Hubby willing/not willing to help you meet the need. (ex: if what is needed is more time with Ben, can Hubby be ok sharing your time)
- Grace is ?
You have a lot going on there with a lot of people having different kinds of wants. You have some limitations you have to work with and then there's other wants that may/may not work together. There's also missing puzzle pieces.
I'd suggest taking it one thing at a time. Ask the people what the missing pieces are and then negotiate to solve it or let go of some of the wants at this time because they cannot happen.
One example of that is the cohabitating thing. Much too soon anyway -- only a few months in with Ben and Grace. AND you have kids and may not want them in coparenting roles. You and Hubby are the parents and hubby doesn't even want Ben to see them on FB. That one at least you can knock off your plate for now by letting go of that want at this time. I made it grey.
Is hubby pushing for more "separateness" because of the NRE drunk? I'd deal with the green one first -- repairing with hubby now that you see you were neglectful on that relationship in your polymath
because of the NRE. That's a hurting
one rather than a wanting one (ex: Grace happy, just wants more time). I wonder if "hubby separateness" and "hubby no ben facebook" fall under the umbrella of "building back with hubby" things or not. I indent them that way in case they are conditions you have to meet as part of "rekindle" -- ask him on those. Are they conditions he'd like you to meet or are they separate issues entirely to the rekindle?
Then deal with Ben feeling this is doomed. That's another hurting
tier. Sort the hurts first.
OR... tell Grace you are willing to her her and hubby to have more time together. There. That's your part in that. Then leave it to them to sort out the rest of the way. It's his calendar. Then maybe you can grey that one off your plate too?