What can I do about my intense love for a woman that is not physical, and which I do not consider to be lesbianism?

If your love for her exceeds moderation, becoming a preoccupation for your mind and dominating your thoughts, then you have fallen into the forbidden area of a woman's love for another woman. While it has not yet reached the point of committing a religiously prohibited act, it could lead to it.

You must cut off these thoughts, turn to Allah in obedience, and distance yourself from this girl as much as possible, while supplicating to Allah to divert it from you.