Welcome Kate,
It sounds great that you have given a name that you like to that side of you that has been with you for 38 years (you mentioned 10 years old as the beginning). Well Kate, I encourage you to use your girl name as much as possible so you can freely express yourself here. Comfort, freedom, expression, and self identity are great powers that all people should enjoy.
I tried the Lands End online virtual model you mentioned. I am very impressed, it even gave a shape similar to the shape of my body. You can even try on different clothes that they sell and different colors. I used it to sort of try out different color schemes with the shape, hair style, and form very similar to mine to see how it affected my appearance. Sure does help. Wish all retailers had this.