Ohhh, i love this question
mainly cos i get it alot...... 
Ok, my favorite responce to this is "Do you not think highly of yourself then?". This i have found to be the prefect responce to this, she means 1 of two things by her comment: either she thinks u believe yourself as brilliant, and she doesnt agree or she agrees. My resonce is a counter to both, she will either respond inplying a yes or a no. If she implies she thinks highly, "so are you always so hypocrital then" and if she implies no change subject since she just DLVed herself which makes you higher value. If she says no, DO NOT NEG. She probably has confidence issues and a neg will be taken as an insult. Either way follow up with a DHV story (be carfull to not sound like boasting, since that will make u sound arrogant rather than confident). The follow up DHV is there to basically show u have a reason to be confident
and it will either confirm her agreement with you being brilliant, or shatter her doubt Hope that helps.
/madals, thinking highly of himself for the past year