I agree with the steamy hinting/email suggestion. I was in a relationship with a woman for 2 years long distance. We had awesome success by just speaking together on the phone about various things, not necessarily sexuality.
I must admit, getting sexy emails was quite amusing... I rather enjoyed sending her messages to her phone when she was in class
I'm evil like that, though.
Oh well... that relationship went the wayside. Ironically, it wasn't until the relationship became close-distance that things started really getting fucked up (pardon my language). It still hurts, I admit.
Anyway, I agree, it's quite... vexing when the person leaves like that with little or no explanation. In my case, I simply had to grin and bear it. Perhaps I would wait a while to cool down (it usually vexed me QUITE a bit... I'm an angry person) until I would call her again.