Mocha- Great BM's dress and color! I think tangerine rocks! Have you tried www.thetiebar.com for any ties? They have a huge variety, and they're usually cheap too.
Tenny- Ugh. People suck sometimes. If you really don't care to have her there, maybe you can gently say that you were hurt by her letter saying that your friendship wasn't the same anymore, but that you re-evaluated things and that you feel the same. Not all friends are in your life for a lifetime. It's like that saying that people are in your life for a reason, season, or lifetime. Maybe her season has come and gone.....and it's okay for you to gently tell her you'd prefer she not come if that's how you feel. I'd hate for you to feel tension on your wedding day she's there with her 3 friends. Try to let this drama roll off of your back.