Ohhhhh, I am so, so sorry to hear this. I was utterly devastated when mine died, and since then I've lost my dad and my husband left me, but nothing has been as bad as losing her.
I so empathise with you. I know this is a huge cliche, but the only thing that will help is time.
As the months go on, something that helps is staying busy - not all the time, but periods of productivity will really help you, while too much sitting and thinking will not. Also, it's OK to take a break from your feelings of bereavement by watching something funny.
But all that is down the road for you. This has JUST happened and you will be essentially ill from bereavement for the next few weeks. That's how you have to think of yourself right now - as being ill.
I send you my deepest condolences. There is no bond like the bond between a loving mother and daughter.
Lastly, please know that it WILL get better, even if it seems unlikely now.