What was the issue that was so important that she had to speak about it in the middle of the night? If it was some sort of personal crisis, sure, you could have spoken to her but if it was just to blabber about things well then no you had a right to say you were going to sleep.

Sounds as if she's going through a few things with regards to feeling down and is projecting it onto you.

I think she reads too much into stuff that simply isn't there. She's overanalysing things perhaps. Insecurity on her behalf?

Either way you two don't seem to be seeing eye to eye and she is feeling some kind of 'void'.

I kind of sit on the fence as to suggesting what to do about it.

You can either view it as 'it's in her head ... it's her issue'

or

Work on strategies that help her feel a bit more secure. But that could be a hit and miss if her self esteem isn't there.