Scotty that's really tough. Your friend was totally unfair and being a bit cruel to make you feel that way. I totally sympathize with how terrible you must have felt.
On my TTC thread, there were a few women who suffered terribly with infertility and miscarriages and even seeing a birth announcement on FB was enough to throw them into a really dark place. I had no idea before that how difficult some people found it.
In my own life, a cousin (who was like a sister) was supposed to be one of my bridesmaids and then pulled out and stopped responding to emails etc. I knew I'd done nothing wrong so just let it go and figured she'd explain herself at some point. She came to the wedding and she explained that at the time she'd broken up with her partner (her baby's father) after he cheated on her and just found the idea of my happy engagement too much to take. They got back together by my wedding (and have been happily married themselves now for years).
I guess my point is, if she isn't generally a bad person and eventually apologizes, I think you can find a way to move forward if its really a close and important relationship. Personal struggles can make people act in ways they are really ashamed of. I'm just grateful I haven't been tested in that way (knock on wood) as while I'd like to think I'm a bigger person than that, I don't really know...