And yes, one thing my W would say to me is that she didn't feel the "passion". Like it was something that is externally found.
They need to fill that void and they are desperate and frantic to find it. Along with equally avoiding that which they feel hurts them.
I used to chuckle to myself (underneath my own pain) that my W claimed to not have any passion, yet she sure had passion to go out to that party and drink lots. Like, to the point of numb teeth and throwing up... *sigh*