The LBS does tend to focus on the OP, which is understandable. Here's the thing. The MR can't work as long as she is turning to this OM to fill her emotional needs. The root of the problem was already there before OM entered the picture. Now that there is a 3rd person, it causes another problem in addition to what was already there.
Affairs of any kind are addictive. The only way to break the addiction is to go cold turkey and never contact the OP again. No FB, photos, nothing!
I believe this M can be saved! In spite of the EA, the bad sex, and the overall bad attitude in the MR. It isn't going to be a short fix.....as you probably know by your experiences with counselors. There are some counselors who offer solution solving methods, and then there are counselors who just want you to talk about everything. If you do not have a counselor who works with you to find a method in solving your problems, it's of my opinion to find another one. I also think you can have too many sources giving their advice at one time, b/c it can cause confusion for the LBS.
Unfortunately, MC will not be successful for your W as long as she is in her EA. Even after she cuts all avenues of contact with OM, he will be in her head for an indefinite period of time. If she realizes she has to help herself to get him out of her head, she'll get through the withdrawals faster. This all has to do with her will and determination to be over OM/EA, and to willingly work to save her MR.
So, the EA is a major problem in the MR. From what I have learned, it's really more about how the A makes her feel. In fact, some women will jump from OM#1 to OM#2, and so on. B/c it isn't really that male person she adores, but rather how he makes her feel special.
If she felt that you were constantly critical, negative, grumpy, etc., it could have affected her "in-love" feelings dramatically. There are several possibilities, considering you saw things changing after the baby was born. She could have been depressed, which happens with a lot of women. If she gained weight, stayed in the house too much, withdrew from others......her self esteem could be suffering. Does she have body image issues?
Some of what you say about her, falls within the description of a WW. Waywards are filled with a ton of resentment (from years gone by until the present time). Waywards blame the H for everything that is wrong in her life. Waywards feel a lot of disrespect for the H, and it will show in her attitude, as well as other ways. (Some women are worse than others). Some H's get so accustomed to his W's bad attitude, until I wonder if he realizes all the ways she really is showing him disrespect.
Resentment, bitterness, blaming, throwing tantrums, entitlement, selfishness, escaping from reality into a fantasy world, lying, acting like a teenager, becoming very private about her phone and keeping it with her at all times, becoming more particular in her physical appearance, frequently going out to bar/party with just "her friends", find excuses to spend the night & weekends away from home without her H .....these are possible signs of a wayward wife (and there are more, but these are enough for now). A WW doesn't have to own all these behaviors, but she usually has most of them. Her anger usually leads her to rebel in some form or fashion. Here on the board, we usually see their rebellion in having an affair....or acting like a girl gone wild. One thing for certain.....she's not the girl you married!
I would like to tell some newcomer H's who have a WW that she does not experience fear or guilt in the way some H's want to believe. Not if she is wayward. You see, most H's try to rationalize why his W has turned into this selfish, cold hearted female from hell. But you can't do it. A wayward is not logical. And as for the feelings of guilt or fear.......if there were any......the selfishness that motivates her, would override it. She is going to look out for herself and how she will benefit the most. I think there are a few things that separates her from the WAW & MLC.......and that is she doesn't feel guilt or fear the way H's want to think they do. They aren't living in fear. Not the wayward! Plus, their guilt isn't there b/c they are going to justify their actions. The guilt doesn't really hit them until the period of remorse comes.....after their fantasy collapses and she experiences loss. As long as she is willfully doing what she wants, regardless of who it hurts.....she is not remorseful.
Long post, so I better stop and save for next time.
P.S. For right now, I would avoid talking about your plans with her. Keep a poker face. Don't get into relationship talks with her.
It is not about what you feel should work in your M. It is about doing the work that gets the right results. Do what works!