you have my sympathies as well as my understanding.
I 'lost' my best friend 20 years ago next month - she took her own life as well. I won't go into the circumstances here, but in life she was a kind, sweet and very shy girl, the least selfish person I knew. What she did to her family (mostly relating to the circumstances surrounding her suicide and the fact that they had already lost 1 child), changed my view of her completely but I guess it was the only way I could deal with her suicide. She did teach me one thing though: I could never, ever do that to my family, no matter how bad things got, and they were very, very bad for a number of years.
3 weeks ago, I also learnt of the suicide of a lovely sweet girl we met on tour who was newly married then. We had only known the couple for 2.5 years (we had maintained contact) but that one has been no easier to deal with either.