I realize this is a very old thread, I found it via google. Not sure if the OP will ever read this response ... but nothing lost by saying it anyway.
Just had to say that I found this a very touching story, 1stTime. I hope you managed to work it all out in the end. My own polycuriousity story is really rather different in character, but none the less many of the things you've said about how you feel seem very familiar to me.
No doubt it's far too late now to issue much useful advice on Lilly, well over a year after your post. But the way I always approached these things is to ask "what would I regret?".
Personally if I really cared for someone, and they were moving away the thing I would *really* regret is if I didn't tell them and it turned out that they felt the same way and were just hoping for me to share my feelings with them.
I wouldn't regret it if I said how I felt and they didn't share my feelings. I wouldn't regret it if they said they felt the same but they really needed to move away and didn't want a long distance relationship. I wouldn't regret it if we tried the long distance thing and it didn't work out. I wouldn't regret it if it made our lives too complicated.
I once told one of my best friends that I cared for her as more than just a friend and she more or less didn't speak to me for the next few years. It was very sad, and it hurt lots, but I don't regret it.
I don't think it's selfish to say that you care about someone, after all maybe that's just what they want to hear. Maybe it isn't, but you don't know until you try. I don't think you can ever do wrong if you approaching the situation with open-mindedness, open-heartedness and honesty.
I also think you were perhaps over thinking things
Speaking from experience, discovering that you may well be polyamorous can be quite an emotional rollercoaster. If you try and think through it all you can drive yourself crazy.
I believe you have to relate to the things you feel in a direct way. If you feel anxious then let yourself feel anxious, if you feel off balance then let yourself feel off balance. Everything we feel is fine, it's our tendency to spin a big story around it that gets us into trouble. If we can sit and be present with the uncomfortableness of it, we can start to find that feeling uncomfortable can actually be rather wonderful.