Tell your DH, your parents and your IL’s “I am very saddened that myself and LO have been through something really difficult, traumatic and painful and you are not able to summon any support at all.”
When they inevitably chime out with how amazing they are, you need to be clear on PRACTICAL things you could do to prove it. What do you need from them? I’m sure you would appreciate being able to spend some quality time with your new baby without having to worry about the rest of life - can they offer help by doing a wash, making a meal, doing some dishes etc?
Tell your IL’s straight that you do not feel comfortable with them telling your personal, painful and traumatic story to strangers without your consent. It is not their story to tell, it’s yours. This is not support, this is using your trauma for their own selfish gain.
“I’ve been through an awful time and I am not ready. I will let you know if and when I am ready to...” Rinse and repeat every time they want you to see extended family members, every time they want to discuss the possibility of another child before you even get the opportunity with the one you currently have
Sit your DH down and have an honest discussion about how awful you feel about the fact he is being a twat complaining about driving when your insides were being ripped open. His inconvenience is not the priority right now. Your health and your LO’s health is important. Sit him down and discuss it all really calmly and matter of fact, so he can’t make some claim about it being hormones.
Good luck OP and congrats on your new baby