I'm surprised that this story is still believed. Short answer, both of them were telling half-truths. I can attest the Black community did not believe Anita Hill at the time, and any very small amount of investigation would show why (although the MSM would never do it and has never put the theory forward). Basically, look at Hill and Thomas' lives: Both came from humble beginnings, both conservative, both Republican. They then start to work together at the EEOC. Supposedly, they were the only two Black Republicans in the office at the time. She was in her late 20's, he was divorced and in his mid-30's. See where this is going? They very likely had an affair. But then at some point Thomas' mentor John Warner(R-VA), set him up with his neice(?), Virginia Lamp. Thomas, for whatever reasons, chose her to be his wife. Years later, as Thomas is about to be confirmed to the SCOTUS, Anita Hill sees him and probably thinks, "That should've been me next to him, instead of that ugly white bi***!" Thus the stage is set for drama. Most people I knew believed this is what happened, and to me it makes sense.
I have heard the same theory from some black friends of mine. They told me that the black community here is dead set certain that she was the "woman scorned" and mad because he married a white lady.
I'm not sure that they had an affair though. My former college roommate was working for Justice Thomas at the EEOC. She testified on his behalf during the hearings, and IIRC she was asked directly about their relationship and didn't say word one about an affair. The impression I got (and I do remember her testimony because I turned on the TV and said, "OMG! It's my roommate!") was that she was interested but he was not. And BTW my roommate would not tell a lie - I know 'cause I lived with her for 3 years and she is dead set honest.
You're probably right that there was more to the story, and definitely right that they were both culpable in some fashion. But that's just the point. He was head of the Office of Economic Opportunity, and it's not a stretch to say that he should never have allowed a personal relationship at the office to take place under any circumstances. It just made him a hypocrite. People may have had office affairs then, but it was seriously frowned upon and grounds for dismissal. What was he thinking?
The other thing to remember is that she did not contact the Committee and demand to tell her story; they called her and demanded her story due to her having told someone about it at the time. She did not set out to bring him down; the president's enemies did.