Contact with a fiancée via the Internet
Question

                As salamu alaykum
I asked a sister for her hand in marriage on-line and we talk to 
each other casually on the internet; is it allowed to speak to her 
even though I am not able to get married until I graduate (in 3 
years). 
was salamu alaykum
Praise be to Allah.
If a proper nikaah (marriage contract) has been done, then you can talk to 
her however you want, whenever you want, because she is legally your 
wife, even if you have not yet consummated the marriage. But if the Islamic 
contract has not yet been done, then she is still a "stranger" (non-mahram) 
to you, so avoid speaking directly to her. As for corresponding with her via 
e-mail or the Internet, there is nothing wrong with doing so, as long as the 
content of your letters is restricted to permissible matters such as advising, 
teaching and so on. But be very careful not to get dragged into romantic 
talk or anything else that could inflame desires or result in something bad.
May Allaah help us and you to obey Him and to avoid everything that may 
earn His wrath. May Allaah bless our Prophet Muhammad.