Thank you all so much for your support.

Yes, she has always been on the small side. This last visit, she dropped from 15% to 10%, but she had gotten sick and was teething at the same time. You would think the doctor would acknowledge the cold (especially since I went to the doctor to make sure she didn't have bronchitis two weeks before her six month check-up) for her % drop. But all the doctor said was, "I think you should start supplementing". When I said that dd hates formula, she was giving me tips to get her to drink it. She (the doctor) didn't even suggest me pumping and supplementing with ebm.
It's also hard because my mother keeps asking, "How long are you going to do THAT?" (and yes, she emphasizes the word). I do have my SIL (who bfed three children), and a mommy group I belong to, but some days you just get tired of the opposition. I am going to join a La Leche League group where I live and I believe that will encourage me.
Again, thank you for your help and encouragement and I will try your suggestions.