You might have to let him feel inadequate next time because it’s true at the moment. His inability to change and unwillingness to take a real look at why has real consequences for all of you. If it were just two adults, you could afford to be more flexible. But he chose to become a father, too; planned, at that. You don’t have anymore time for him to TRY to grow up. He needs to do it or let you guys go. You might have to make that choice for him; doesn’t seem like he’s equipped.