Venting about friend

I just hate feeling blown off by a close friend. Especially one that knows what's going on emotionally/medically with me. She seems to get very wrapped up in her own life at times so she over schedules stuff so then blows me off, and can't even like call me, she sends me a freak'n email. This entire time I haven't heard from her: I thought she was mad at me, or something was going on with her and her husband, I left her a message/emails asking if she was ok. I was totally concerned. It's unusual not to get at least a text or two from her during the week. (She also has some issues with anxiety and we've basically have been support systems for eachother.) We made plans over a month ago because our schedules are so opposite, I get work comes up but if she at least called me. She's done this before: I was the maid of honor in her wedding last year, and she turned in to a very snotty person, would like not talk to anyone or be very mean. No one wanted to talk to her, I ended up talking to her and we sorted stuff out and got through that rough patch.
I'm just sad that this is happening again. I don't want to loose my friend; I don't trust alot of people.

Sorry, I totally needed to vent. Thanks for listening!

I think recognizing your friend over schedules stuff is good insight...I have a friend who sometimes displays manic type behavior and is just all over the place, and it becomes pretty tough for us to schedule time together. So I can understand the feeling of being blown off...its important to have an open, honest, caring discussion about your concerns.