This can not be customized using theme options. The files responsible for my account page are included in folder folie/woocommerce/myaccount.
Please keep in mind that personal customizations are not supported.
You can edit the text in these files: june\woocommerce\header-login-box.php
june\woocommerce\myaccount\form-login.php
Or use the pot file to change them. See this article for more information.
