I found the only time the nausea went away was when I was eating 😅 maybe try nibbling on something plain to see if that buys you enough time to get to sleep? It is tough but it will end eventually. Also I find listening to some nice music or a soothing podcast can help relax my mind in the wee small hours (especially now when my newborn feeds a funny times of the night)
I’m always sick between 8-9 then continue to feel sick for hours after to. It’s awful! I’m trying Gaviscon after meals and sickness bands but they don’t seem to make a difference x