Arthurian Legend

This is part of a regular journal post, but since most of my readers would be clueless, I had hoped some of you here might help. "Teryn" is the working title of my book. Teryn is a servant and confidant of Guinevere. The premise of the story is that Gwen and Lance knew each other back in the day. She wants to be a good wife to Arthur, but he has already slept with Morgan, who may or may not have enchanted him (most likely not, since Arthur already hit on Teryn). Morgan is still pretty flamboyant about being the first to carry an heir. Teryn, Merlin, and Nimue know that Arthur and Morgan are kin, but Guinevere does not. She also doesn't know that the baby is Arthur's. To alert Guinevere of this would mean major war/destruction... at this point in the novel, Guinevere is managing things on the homefront while Arthur is beginning to enforce the security of Lyonesse before moving the base of operations (per se) to Camelot. Basically I am writing Guinevere as a "once scorned, watch out" kind of character, with a major aura of power in her own right. Teryn is timid around Guinevere but speaks out when asked... her main conflict will ultimately be choosing between Guinevere and the Goddess... or possibly even confusing the two.


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Anyways, I managed to write some Teryn tonight, more than a page. I've been writing more sporadically than before, but my page count is catching up to missed days. I have a few things to work out:

1) Blame. This is something that even Marion Zimmer Bradley could never get around. She still had to lay blame on someone, even though she blamed patriarchy. I face the same problem. My main character is somewhat attracted to Arthur, so to see all the blame on him and through her eyes makes no sense.
2) Morgan le fay is already villanous, but I don't want to fall into the trap of blaming everything on her, just so that I can absolve Guinevere and Lancelot of blame... this makes me put more blame on Arthur, but I still show that he comes through as a noble king.
3) Lancelot. The dude can't be a sex object/flat character. Not only does that make the story less interesting, it makes it totally unbelievable that Guinevere truly loves him.... why would she love a random hot guy? She wouldn't, it would be lust. So I have to concoct some sort of scene in which Lancelot does something other than save her in some sort of distress... in my version he is very learned, so perhaps I could show him as a reluctant teacher of some sort...?
4) Curses and enchantments. I can imagine all of the neato pagan rituals that I need, but I'm having trouble with how a curse would be done. Mostly because in my own personal investigations of spirituality, I haven't really confronted dark magic, or even Wicca, really... other than looking at principles of it which apply to me. So how do I have a convincing curse?
5) Anyone know what herb found in Britain might rid a woman of a child, and is tasteless?
6) is it too risque for my main character to poison someone who bears a child? I want to convey that Teryn is fiercely loyal to Guinevere and has this main conflict between being loyal to Guinevere and being loyal to the Goddess... often she may even confuse the two... how should I write this?

Basically I have to make myself un-mary sue a bit more than i had originally intended to give this character a mean streak. I have never had my loyalty TESTED in this manner. I probably wouldn't be able to do it. So I guess this is where my ability as a writer is tested.

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suggestions welcomed, thanks!!!!