Just don't say insensitive things, and be careful about what you say. You said you're far away from her? When I have a friend going through a breakup I try to hang out with them to keep their mind off things. My friend is going through a breakup now with a guy that cheated on her for over a year (she just found out). I just don't say "I told you so" and ask her a lot of questions, relating to the relationship and how she's feeling.
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After a time, you may find that having is not so pleasing a thing, after all, as wanting. It is not logical, but it is often true.
--Spock