Belligerent

Being hostile, looking for a fight.
Being aggressive, combative and intimidating.

Susan is like this most of the time. She’s so easily upset, so easily offended, her demeanor is generally belligerent.

She constantly spews belligerent trash-talk (vitriol) during her many devaluing sessions.

Examples:

Susan was spouting all kinds of belligerent insults my way.

I receive enormous amounts of belligerent vitriol from Susan.

Her whole demeanor quickly turns belligerent when I try to reason with her.

Attempts at collaboration generally result in belligerent outbursts.