Putting it in the context of Skin Games. Anduriel is precisely the point.  Butters confronts Harry and Harry tells him that he can't tell him.

But that is a little late, Butters is already angry.... If he had been in the loop in the first place, i.e. clued in by Murphy who presumably is leading the fight against the Foman, he wouldn't have had to confront him nor would he have a reason to be afraid of him..  Even if Harry cannot tell him the exact reason, Butters would understand that it is a good one...   

So Butter's doesn't keep silent. And Harry stonewalls him. There is about two pages of dialog that covers most of the points raised here prior to the part I quote.   

Bob is FUD on the hoof.  Jim uses him both as a talking head and as an all around confuser

You are missing the whole point...  If things had been explained to Butters a couple of months or so before the big chase in Skin Game, the chase wouldn't have happened in the first place because if Butters knew there was a good reason for Harry to be away, even if he couldn't tell him at that point in Skin Game what it was, no chase, no FUD moment, end of story....

I think what's being said here (and certainly what I'm saying) is that Butters should/would have said something before Skin Game.

Exactly,  his anger and fear has been building up way before the chase in Skin Game...  Murphy and Thomas both know there is a good reason for Harry to be staying on the island..  If Murphy was playing leader of their defense group, no reason to think she wasn't, she was in Ghost Story, as a good leader she should have been able to read Butters... Then she should have took him to one side and even if she couldn't tell him exactly why Harry was away, say that there was a very good reason that will be explained later... Or who knows Butters may even have come to her...  Something is missing in this picture,  understood Butters is very upset about those kids, however he has always been the most sensible of men, thus he may not like Harry not being there, but at the same time understand it isn't really Harry's choice... 

For me the huge unanswered question is did Murphy or Thomas ask Harry why he won't leave the island?   We know they visited him, why wasn't there a come to Jesus moment when they confronted him with a "look people are dying left and right we need you!"   If there was, did Harry answer them
truthfully?  He could have answered one of three ways, 1] "this is the only place where the pain in my head won't kill me." 2] "Mab will kill me if I leave, she has me watched..." 3] " The defenses of the island are in a neglected state, if I leave now, worse than the Fomen will escape.."  The one thing I doubt he'd say would be he didn't give a crap about what was happening back in Chicago...

My other question is why neither never defended his reasons for not being there to Butters?  Butters is a just and intelligent man, if he knew the above reasons he may get frustrated because he felt they were powerless, but he wouldn't have blamed Harry like he did.

We all know Murphy by now and it is unlikely that if she felt Harry was really needed she wouldn't have pinned him to the wall until she got an answer as to why he wasn't coming to their aid... So
here is an explanation most will not like...  She may feel that they ran things pretty well when they thought Harry was dead.. May even have liked the power that brought, the importance, after no longer being a police officer, she didn't want to play second fiddle to Harry...  Or for all her talk of trust, still a part of her never fully trusted Harry after he became Knight.   Otherwise I cannot account for the attitude of Butters towards Harry..   There is a missing part to this puzzle...

While Michael is Harry’s best friend, that designation has waned since the whole deal with Lash - instead Harry grew closer to Murphy in the meanwhile. Given his religious beliefs, Michael is also somewhat limited in that capacity - Harry constantly has to watch his cursing around Michael & mentions how uncomfortable Michael was with certain aspects of his relationship with Susan in GP. At some level, Harry wants to impress Michael & be worthy of being his friend because of what a thoroughly good man Michael is - Harry’s relationship with Murphy is on more equal footing.

All of that is true, however since Maggie came on the scene I believe they naturally will get closer again.  Michael's place was her home up until now, Harry may turn to both him and Charity for child care advice.  Though what happened to Molly may put a crimp in the relationship.

According to Murphy, her second husband wanted her to stay at home because he can't handle Murphy having a better career in the police force. From what he did in book 6 by marrying Murphy's sister and Mama Murphy's reaction, what Murphy say has quite some credibility.

Perhaps, but that hints at more complex problems under the surface...  Didn't he go on to join the F.B.I? 

From what I see, her 2 previous marriges fail because both of her exs is not strong enough to handle her. Murphy is too compotent, and becoming the spouse of such a woman is never easy for your average man. The same reason why a successful and rich career woman tends to have a hard time finding a husband in real life. The problem is not on the woman, it is on the man. It is easy for a strong man to marry a weak woman, but vice versa?

Or perhaps has bad taste in men?  Usually the problems are not quite that one sided.  Quite often if the pair are on an equal footing things fall apart because both are so busy there is no time for the marriage...  Weak men marry strong women all the time for various reasons..  It also depends on how you define what strong or weak mean in either sex, it isn't just about who had the best career or makes the most money, one may want to be controlling, another may like being controlled...

Karen  is going to be regulated to being a side character. she is eventually is going to Mary Dresden and take on the role of step mother to Maggie.  this is not going to mean she is written out of the story it just means she will no longer be seeking to be the one who takes on the big bad monster. I am sure she will still have times that she does bad assery and kick some supernatural butt. now it will be her avoiding it but every once in a while being forced into kicking butt in defense of loved ones.

I think that would be a very sad ending for her, better she go out in a blaze of glory.

Why be confuse on where her path may lead? End of skin game has show us exactly where her path may lead. Well, at least in regards to her psycological and emotional health the signs are all good and clear. If we are talking about this issue at the end of book 13 or end of book 14, then yes, I must agree with you that Murphy is still in a bad place. End of skin game however, put an end to this issue. Unless future books show otherwise, I see no reason to assume negatively about Murphy's psycological condition.

Are they?   I don't think we can assume anything,  last time we saw her she was in a hospital bed on pain meds..  Yes, Harry kissed her and gave her a small fortune in  diamonds, so yeah, at that moment she was in a happy place... But we've heard nothing one way or the other since then...

Her character always drove me nuts until I realized that. Her antagonistic relationship with Harry in Storm Front makes sense. It doesn't in Fool Moon, at all. After that, Murphy's pretty level for a while, but every time we see Murphy playing politics, she's making the most aggressive play that's guaranteed to piss people off who she might need in the future. Then there's her plot arc of trusting and not trusting Harry in Ghost Story/Cold Days/Skin Game. (The part of that arc that really annoy's me is Butters doing the same thing). It's rational in Ghost Story, at first. Then it's not but still understandable. Her hesitance to trust Harry in Cold Days makes sense, too. Her approach is still overly aggressive, as always. And then in Skin Game, she just completely trusts Harry even though he is being super secretive and working with a guy the Devil keeps at arms length. For reasons?

Did she?   Like KurtinStGeorge I won't go down that rabbit hole again... Suffice it to say that her actions got a Holy Sword broken that day..   To quote Measter Aemon, "love is the death of duty.."
Bad for a man of the Night's Watch, and for a career policewomen as well, she might be retired or fired from the force but she still is one, in her heart..  It could have ramifications later on... Just saying..

"Christ, Harry," Murphy said quietly. "No one just starts giggling and wearing black and signs up to become a villainous monster. How the hell do you think it happens?" She shook her head, her eyes pained. "It happens to people. Just people. They make questionable choices, for what might be very good reasons. They make choice after choice, and none of them is slaughtering roomfuls of saints, or murdering hundreds of baby seals, or rubber-room irrational. But it adds up. And then one day they look around and realize that they're so far over the line that they can't remember where it was."

I really wondered when I read that if Murphy wasn't referring to herself in the part I highlighted.  She was in a pretty dark place emotionally in Ghost Story.  We know she terminated two sorcerers with extreme prejudice before ghost Harry showed up in that book.  I think there is more to Murphy's story that we haven't heard yet, and before we do it's difficult to know where her path may lead.

It isn't new for her, the aftermath after Nightmare got into her head was she turned to the bottle.  Understandable maybe, but she wouldn't let anyone help her that time either...  Murphy may seem
very tough, but there is a brittle component to her personality, I repeat it wasn't just her body that Nic damaged...