IMO you are asking allll the wrong questions...

The question why your future MIL won't allow you to anything obviously doesn't get you anywhere.

The question you should be asking, is why two grownass people think they need anybody's permission to do ANYTHING...

You've posted numerous questions about why you can't get permission, what kind of consequences or damages will ensue and people have answered as best they can.

I think what keeps you posting on the same topic is the fact that you're asking the wrong questions and thus receiving the wrong responses...

You guys are in therapy, so use it to your advantage. Ask the therapist to help you transition into independant adults, thus making your own decisions, and in so doing, live the life you both want to lead.