Do you think online friends are as good as ones in real life? Why and why not?

My worst experience with an online friend was with a lady whom I met on EP and who introduced me to SW after EP closed. Nearly three years ago she suddenly stopped talking to me in the middle of a PM conversation (about classical music of all things) which she had initiated. No explanation, no replies to my messages or emails, nothing. She (or, I suppose, someone using her account) still appears on SW from time to time, though not as much as she used to, but ignores any contact from me.

Of course, real life friends can dump you too, but usually they have to say goodbye and you can find out what the problem was, one way or another. Online friends can just disappear if they want to. 🙁