@Ahorsecalledseptember
I'm really sorry your baby is not sleeping either. It's impossibly difficult.
To answer your point about babies sleeping in the womb. In the womb babies are constantly held, constantly warm, constantly fed. They experience movement, the loud rushing of blood and your heartbeat. They fall in and out of sleep with no input. It just happens. The transition into the outside world is a shock - imagine feeling hunger for the first time, light, air, coldness, being able to move your body (not even knowing what a body is) for the first time after the holding constriction of the womb. That's the idea of the fourth trimester we're banging on about. Human babies are born so early in their development. For the first 3 months ideally they need as much of that womb-like state recreated, slings, being held, on demand feeding etc etc. It's why white noise can help with sleep. And movement. And swaddling. It's all recreating the womb.
The thing is, we have needs too. And sleep is obviously one of them! In many ways the fourth trimester is great for mum too. It encourages you to rest, to be as inactive as possible as your body transitions from pregnancy and heals from delivery. It's absolutely ok for you to have needs still and for them to be met, it just might be very difficult at this stage.
We're not meant to be alone at this time, not even in just a couple. Other cultures do this time very differently, with a network of support, so that mothers only have to tend to baby, they don't have to feed themselves, clean, and in some countries even wash - they are washed and warmed and massaged.
But that's not reality for many, far from it. And it's even harder at the moment in a pandemic. We have even less support than we might have done. It's incredibly difficult.
But it's not you and it's not your baby, being anything other than a baby. That's why we're recommending reading about normal infant sleep and the fourth trimester and forgetting about routines for now, just focusing on survival, and understanding that unfortunately your baby might not sleep as much as you need, or for long periods, even if it seems counterintuitive and you think it's what they need and therefore they should. Even with all the help in the world your baby might struggle to do things they need to do.
Birth experience can play a part too.
Honestly, it's really worth looking some of this stuff up. It might help.
It's incredibly difficult becoming a mum with the huge transition into motherhood, change of identity, hormones, anxiety, and then the sleeplessness on top. It's awful. But I'm afraid it's terribly normal. I feel sick saying that because I really, really do know how awful it is and I hated it so much. It's still hard now but not the same intensity.
It won't always be like this.