Actually, yes, an MLC spouse could trigger the LBS into crisis. Generally it can occur once his crisis is just about over. However, I don't think that's what is going on w/you.
The photo incident and the WAH sister have got you spinning. The sister doesn't have a clue as to what is going on and until she walks in your shoes or anyone's shoes that are dealing w/this, she needs to step back and keep her opinions to herself. Only you know what your life was like pre-crisis. Was it real or memorex? Only you know.
Give yourself a break....you've got a lot going on and yes, we all have days just like yours when we question everything. It's normal!
Sit quietly, the answers will reveal themselves when you least expect them to. The past is gone, the present is a gift and you need to focus on today, allow the future to reveal itself when it is ready.