Some studies that my husband was telling me about show that if you're insecure and you have power, that you abuse that power. So it's doubly important, as you grow in responsibilities, to take those insecurities out and slay them.
For me, the best insecurity slayer is to know that God loves me, cares for me and even when bad things happen to me, He can work it to my good. He has blessed me so much that I must, must rejoice in others successes and enjoy the unique way He made them. Probably not perfectly said nor precisely accurate, but one thing I'm sure, is that I must, in 2010, slay my insecurities. The Proverbs 31 woman smiled at the future. She was secure.