Hi - sorry to hear things are not going too well.
You could try a blow up bed in DS's room - that way DH won't be cross and you'll be able to soothe DS easier and quicker which will also give you a bit more sleep than doing WIWO.
Unfortunately, it only takes a few nights of doing something to form a habit
It took us about a week to get back on track after DS's ear infection during which time he was in our bed from midnight onwards most nights.
He would wake in the night crying and pointing to our room and saying, "Daddy, Daddy!" Ohh my heart broke! It's very hard not to cave in but you just have to think LONG TERM and definitely get to bed earlier at night to catch up on sleep. I was REALLY tired
But, also remember that DS may still not be feeling 100% although he's ok during the day.
I really hope things get better soon. It's soo hard to cope with things when you don't have enough sleep.
Lis
x