Disclaimer: I'm not an admin on this wiki either. But I've read and reread these books many times and I'll add my two cents on what I think the statement means.
Given the context, to me it sounds like Kylara notices she has a bruise on her arm, thinks about covering it up so T'bor won't wonder about it, but isn't too concerned because she can just blame it on him since he doesn't remember his actions when he gets drunk.
That doesn't necessarily mean he hits her when he's drunk; just that he doesn't remember what he does when he's drunk.
Now there might be other passages that more explicitly suggest T'bor hits Kylara; if they can be found, then the information would be valid.
Like I said, however, just my two cents.