Falling in love over the internet or phone... Quite possible. If they are both honest and open with each other, they'll be seeing parts of the core of the person. The body and mind changes with experiences and age, but I feel there's a "core" of a person that we search for and want to be attracted to for a lasting love. In some ways, it might be easier to find that core without the distraction of the body. In some ways it might be harder, because so much communication is indirect.

As for a healthy marriage? I don't know. I'm still learning about what a healthy relationship is.