Well, about 2 weeks after my wife gave birth on one particular day I got up at 5 to let the wife sleep for a few hours while I looked after baby, started work (at home) at 9. Stopped to make a cooked lunch, did a nappy, cleared up, worked til 5, cooked a dinner with extras for the freezer, cleared up, bathed baby, nappy, poonami, another bath, then took the dog for a walk. Whilst on that dog walk I walked past a pub. It was cold and raining and I could see the open fire from the road, so I went in. I sank that single pint in 10 minutes and went straight home. Unfortunately the wife caught me on life360. You'd have thought I'd spent a month on Ibiza snorting drugs off strippers. I was the worst man alive, teary calls to the mother in law, my own mother was called, even threatened with social services.
That was terribly harsh on me, she wouldn't have blinked an eyelid if I'd have gone 10 minutes further with the dog.
The point to me recalling this incident is to illustrate that of course OP is being unreasonable from a rationale standpoint, but when you're sleep deprived, overwhelmed with new responsibility and traumatised, rationality and fairness go out the window.
I think the DH should be ok to go out, especially given that you're with the inlaws, but a bit of conversation around how you'll manage and mitigation on not getting drunk, not being too late etc. might make you feel better and more cared for.