Well it is due to an excessive attachment that is afraid about losing anything (and includes the loved ones as part and extensions of oneself) including name. The good part is that you understand it is harmful for both of you and hence are open to change. The best way is to pray to God to free you from this and all fears. Along with this you need to cultivate faith in the Divine Grace that all will be well and the destiny of your child does not depend upon these competitions. Remind yourself that each child has his own unique destiny to fulfil which he will fulfil with help from God.
This need to change is the first thing needed. Then a steady application of the will in the intended direction. In due course of time you will get over it. Read inspiring memoirs of those who failed and yet went on to rise to great heights.
Affectioneatly,
Alok Da