This sounds a little familiar. Im currently pregnant with my second and with live in the granny flat PIL built for us when i feel pregnant with my first. I think the whole protectiveness of their boys is quite a common thing and because you are technically under her roof then its easier for all to abide by her rules iykwim?

We are moving out hopefully by the end of this year. I think DP will notice some changes when we are out on our own as i am not his mother, and dont except being treated like it. So im hoping things will change for the best and he will take care of his responsibilities.

HTH

Simone