Planning before deployment?

My husband's family has invited us to go to the coast (gulf coast) during the block leave he will get prior to deployment. We live in New Mexico so it would be quite a drive through the desert areas and through large stretches of nothingness. I will be 9 months pregnant, but still a few weeks from my due date. I told them I could not do that because if I go into labor on the road it could be bad. So then his mom offered to fly us out an when I told her they won't let women in their third trimester fly due to air pressure changes causing labor, she looked at me like I was purposefully trying to ruin her plans. Then I said that my hubby can go without me since it will only be a week with family at the beach. They all said no to this but now I feel like the bad guy because my hubby will be away from family for a year when he gets deployed so I know he wants to go. What would you guys do?