If he wants his parents to come visit, then maybe it's time that they stayed at a hotel nearby. After all, you both have work schedules and other obligations that may not allow for you to be at home when they are there. I would hope that they would be understanding of this fact and be willing to stay nearby.
It's okay for your h to go visit them at the hotel and maybe even have them over for dinner one evening, but to come stay in the home while you both work...I wouldn't like that either.
Sit quietly, the answers will reveal themselves when you least expect them to. The past is gone, the present is a gift and you need to focus on today, allow the future to reveal itself when it is ready.
