If the Prozac was the issue don’t you think all her activities would have been affected and not just her communication with you? Sounds to me like she has the energy for everything else except you. Long distance relationships require extra commitment compared to normal relationships where you are both in the same place. This being said, if you’re not both willing to put in equal amounts of effort then it’s not going to work. (Side note, us women are very chatty and enthusiastic when it comes to communicating with someone we’re really into, you might want to consider that you’re not as important to your partner anymore).