I believe both of them.
I've covered that ground in my recent article - and this case was an interesting lesson in how to win a case. I think it's very likely that he did hit her and they were both likely hitting each other. I think it's very likely that she had some mild bruising as a result of an altercation. That should've seen his defamation suit thrown out and that was her legal strategy to win.
But she may also have false beliefs about what happened and may also be projecting her behaviours onto him as a form of psychological self protection. In allowing her to lead and set the scope of the case, the legal team didn't stand a chance. I don't believe she's lying, but I also don't believe she has an objective grasp on the truth either. That's a complicated place to sit, but I think it's the right place to be for these two people.
I think the FOS argument is problematic, freedom of speech has never covered the right to defame others. She is free to say whatever she likes, he is free to prosecute her for libel if he can make the case. It was an unlikely win at the outset of this case - but it was an important win for society moving forward.