I too would ask her outrite. The only problem is im not one with words - please see my post and give me advice too- but as i have discovered over the past couple of months honesty and being fully explainable with your actions is definietly the best way to be with someone. Ask her; she can only say no and what would you have lost - nothing you can still be really good mates like you are now!!
Go for it! and Good Luck! let us know how you get on.