It is really hard to just STOP talking with someone..that you spent almost every day talking with either on msn or phone or whatever.
It is gonna take some time to get used to not speaking with her, im guessing she has your email addy so if she wanted to contact you she could.but removing her from your msn is a wise decision, and deleting her mobile number also.
I wouldnt even think of getting into another relationship whether it be online or in RL... not just yet anyhows.
You need time away,, and slowly as the days pass by you will think about her less and less.I ve been through it and it isnt easy, but if all it does is cause you stress then it isnt worth going through it.
Take time away from the pc, go see people that you know offline, start a new hobby or something, you will be ok,, time heals hun.