I am so sorry you are feeling this way. I, like many others on here have been in this position its horrible.
My mil went from staying a couple of days to 2 weeks I think from memory I swear I'm still scarred. That 2 weeks did go by quicker than I thought PLUS I vented on BH a lot haha so the support from here honestly got me through. Why why why inlaws even stay I do not know if your DH can get them to stay in a hotel it would be good but if he's like my DH it won't happen.
Hun you will get through the next few days you will and then it will be just you and bub again.... I am sending you the biggest hug right now..... I feel your pain
Edit: oh yea thats right and my mil cooked 2 meals I think in the whole 2 wks some days DH and I went without even eating because the baby had severe colic and there wasn't anything on hand