Hey there~ I would just call her and ask her about it. Since you guys are B/F's, it shouldn't be a prob and she should understand. I would just jokingly say," So, I am one of your bridesmaids, right? Because you never gave me the official 'go' on it..." And kinda chuckle. When you are planning a wedding and newly engaged, you know how it goes... maybe in the excitement she forgot to ask you and assumed you knew. I hope that this helps! Good luck and let us know how it turns out! It sounds like you are a BM, she just hasn't "asked" yet.