hi 4getmenot,
the same thing happened to me a few years ago, my fella was away in the navy for 6 months and 2 days before he was due back he txt me and told me he was seeing someone else. in my head i knew he wasnt coming back and was just a t*rt but i was scared that it was because he didnt fancy me or that it was my fault and that no1 would else would want me so i guess your friend is prob feeling like that too. but i agree with you, you shouldnt make excuses for people like that because she prob knows its not true! it sounds like shes in denial and trying not to blame herself for it and in a few months will prob see that you was right. and dont feel guilty for what you said, everyone has different ways of dealing with things. :)
not very helpful but i just had to share that with you lol.