My advice is to treat her as a friend. Because that is what she is. You are 6 months into a separation from your marriage? I assume that means that you aren't divorced legally yet. So deal with that. Your friend is acting the exact way she should be, whether she has feelings for you or not.
So don't think about things like you having feelings for her. Concentrate on getting your stuff together and being in a good place. Only AFTER you are in a good place should you think about new potential romantic partners.
Good luck.
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