MC, mediation is not "required", but it happens to be the very first order of business from a judge prior to actual D proceedings.
The "mediation" that W and I entered into earlier this year was voluntary, not court-ordered. W hired the L who acted as mediator and I payed half the $200/hour fees.
Yoyo, I sent W a letter a couple of weeks ago now -- I told her I was done with her so-called mediation given how poorly my interests were treated. I told W in that letter we had but three options (1) hire another mediator (one we both agree we could accept), (2) each hire our own attorney under a Collaborative Law agreement for a four person mediation, or (3) a costly court battle.
W indicated that she'd take option 3 to get a temporary custody order established.
The funny thing is that if we go the litigation route, as I mentioned above, in this state the judge will send you to court-appointed mediation first thing anyway.