Maybe she could just really use the money because she's in a tight spot and you offered,, So give it to her, how embarrassed do you think she will be if you let her know that a; you found her out and b; you asked everyone in Dulwich about it? If she's your freind, she will have a concience about it and owe you an unspoken favour which you will be both be aware of. Isn't that what friends do for each other? besides it was her birthday wasn't it? hugs as ever