So... a few intense/yucky msg-txt conversations later and one in person meeting today that was serious, but not yucky... I have come to a number of conclusions.
1 - Morp has some pretty serious trauma/abuse/betrayal in his past, which leads to him having a hair trigger on some issues. This may/hopefully will improve in the future.
2 - We are not suited for a D/s relationship. Kinky play sure. Top/bottom/switch (reasonably low risk kinks), ok. Authority transfer? uh, no. I don't have a need or desire to completely change the way I am submissive, and he has no need or desire to be the type of dominant I want. So that's done.
3 - He gets into snarly moods. He takes them way less seriously than I have been. We will be improving communication - in that he will tell me when he is being snarly and I will be leaving him alone until he is in a better mood, rather than trying to fix/talk/do something to help, which actually ends up making it worse. If something serious happens, after he is done being snarly all by himself, he will come to me to discuss it calmly. Same with myself; I will need to be snarly by myself and then speak calmly afterwards.
4 - We have completely different relationship styles. I'm more like LovingRadiance - in which if I'm in a relationship with someone I tend to want them (and their kids, etc etc) to be "part of the family". He's more like London - in which everyone is completely separate, very private, very autonomous. He is absolutely very independent, and touchy about anyone having any real control over any part of his life or being able to figuratively tie him down in anyway. So part of his refusing to provide information about himself is due to his past history; and part of it is due to his need to retain complete autonomy.
5 - If I have any hope of keeping this relationship, I need to back off - let go, let it be, stop trying so hard. I over-analyze and am prone to huge emotional swings - devastated if he's angry with me, joyful when he's happy with me, etc - and I need to decouple that. Norwegianpoly had a good point ("acting like a wife") - I was acting a lot more like I was, as my grandma would say, "attached at the hip" with him, and less like a woman in a still new, essentially dating, relationship. Not only was this confusing to him (as mentioned, he takes his own mood swings far less seriously, and didn't understand that they affected me so intensely), but it was spilling over into Guy's and my relationship. So much so that Guy and I had a serious talk about the emotional tide coloring and tugging on his and my relationship and that he was unhappy about it. So I will be working on letting the relationship with Morp be what it will be. It is definitely going to be more a 'casual friendly relationship' shape than a 'another 24/7 D/s co-primary' shape.
6 - Morp has less knowledge about the internet and how it works than I do. I would like someone to remedy that (if only so that he can be as private as he likes but currently isn't), but at this point he's not about to trust me to look at his accounts more than the little (public!) information I've already seen. So until he decides that he's going to learn more and fix it himself, I just need to limit online interaction with/regarding him to fetlife and chatting. I have Pidgin, which enables me to connect with and message via any of the IM services he and I are signed up for, without having to sign into any of them on their own websites. (So if we're chatting via google chat, for example, I have no chance of accidentally seeing something about his kids from google+.)
All in all - thank you all for being here. Typing things out often helps me clarify my thoughts, and you bring up points I wouldn't have thought of otherwise.
Guy - Dom/husband
Minx - sort of dating
Cru - (no longer dating)
Lee - Guy's girlfriend