Harassment: "the act of systematic and/or continued unwanted and annoying actions of one party or a group"
So, there is no clear cut answer to your question. one woman may welcome your company in which case it's not harassment. Another woman for find having people sit at the same table as her to be annoying, thus constituting harassment. the problem I have with harassment policy is that in contrast to most policy, it's not defined by what you do, but rather by how another persons feels about what you do. I think that's very problematic. I might sit at her table and it's not harassing, and you might sit at the table behaving the same exact what and it is harassing all because of how she feels about it.
It's getting even worse than that. Choosing to sit at another table and leave her alone can also be an unwanted or annoying action from her perspective and also be considered harassment. While you can make some educated guesses that may reduce your chances of being accused of harassment, the reality is that harassment policy is worded such that no matter what you do, (or don't do) you can be accused of harassment.