@xuanang01 This is such a hot topic. But most importantly
YOU NEED TO GET MORE SLEEP. As you said, flying that sleep deprived is incredibly dangerous. You need to figure out how to do this. If your partner can take on some more of the sleep debt safely, consider that.
Re: bedsharing...
I've seen a few people already post links or topics I was going to suggest (BC gov't page, issues with separating safe bedsharing from all bedsharing, different countries including/excluding certain deaths in SIDS.)
Note that the gov't page linked by another user does NOT recommend bedsharing. The Canadian Pediatric Society just recently acknowledged how prevalent bed sharing is (2/3 of parents will at some point) and so felt it prudent to release guidance on how to do it as safely as possible.
We weighed several factors in our decision making. We wanted to try and follow best practices as much as possible. But at 4 months sleep got hard and he out grew his bassinet.
"The NICHD notes that SIDS is most common when an infant is between 1–4 months old. Additionally, more than 90% of SIDS deaths occur before the age of 6 months old." This fact made me more comfortable bedsharing starting at 4 months.
We also discussed it with our doctor, and were ideal candidates based on the safe sleep seven.
My advice to new parents is always to research the safe sleep seven, but try to follow best safe sleep practices as much as possible. A sleep deprived parent is more likely to accidentally fall asleep with their infant in an unsafe sleep environment if they are unprepared and uneducated on how to do it (relatively) safely. I loved bedsharing honestly, it worked for our family, but I do
not think it should be plan A and is not our plan A for our next child, at least not for the first 4 months. It sounds like it may be time for you to move on to plan B... whatever that may be.