If I were in your shoes, I'd share my concerns with P-Vine, ask her what she makes of it and go from there. If she is enjoying the emails, let it be. I've PM'd with someone right here on Mudcat several times over the last 24 hours, it doesn't make me obsessed (or her) but rather we are having a decent exchange. Would you have the same concern if this woman was not a lesbian?
If, on the other hand, she's uncomfortable and not sure how to handle the situation, offer her some suggestions. Sometimes it's difficult to politely get a message across and another point of view is helpful.
And hey man, whatchoo digging up around your garden these days?