Yes, I did remember that you went before. The problem I have is that many of them really aren't that good. I spoke to six of them, met with three, and finally found one that was good.
If I were looking for a fast runner, it would be easy to figure out who was the fastest, but there's really no way to evaluate how good an MC is until you've seen what they have to offer in person.
In terms of what to tell them, I would walk in (by yourself) and basically explain that you're so frustrated with your marriage that you don't know if it can be saved. I would tell them that you're motivated to stay together for the sake of your son, but the situation with your H is such that you no longer trust him to do anything he says he's going to do, that you feel he's disrespectful, and you just don't like him anymore. I would also try to share H's perspective.
Then, I would ask them how they intend to help you?
The other thing I insist on is the ability to send all the background info via e-mail first, so you don't get charged for a session just to cover the groundwork.
Of the 3 MC's I met with, one was going to focus on "reflective listening exercises" and saw communication as the way to solve anything. That wasn't going to work for me, we actually communicate quite well -- that would have been a waste of several months.
The second MC was going to take the "childhood experiences" path, how those experiences have shaped who you are, what hurts you have that need to be addressed, etc. That wasn't going to work, W isn't interested in going into her childhood hurts, and that approach isn't solution based.
The third MC (who has published 10 or so relationship books) got right to the issue that W did not feel "safe" in the marriage in that she never felt like she was good enough, and had some ideas for what could be done about that.
It's when you get those "ah ha" moments that it's worth proceeding.
Accuray
Married 18, Together 20, Now Divorced M: 48, W: 50, D: 18, S: 16, D: 12 Bomb Dropped (EA, D): 7/13/11 Start Reconcile: 8/15/11 Bomb Dropped (EA, D): 5/1/2014 (Divorced) In a New Relationship: 3/2015