Been happening for a few years now.
Only ever happens when I sleep alone (non resident partner most of the time - he is here maybe 2 nights out of 7 ).
I am wakened in the night by either my bed shaking (or at least that what it feels like) not violently just a gentle shake.Or alternately I feel someone is sitting on my bed.
Usually I am so tired and annoyed I just think 'Oh hell it's that weird earthquake shakey bed thing'However last few times I have made a real effort to check I am awake- biting my inside cheek etc- and it is really happening.
Too scared to open my eyes.
Tell me the logical explanation - dont live near underground or railway UK-so unlikely earthquake.No pets.