I've always struggled with the morality of this.
However, as my Professor pointed out, fabricating the details of my past to certain people will not hurt them and I do keep the responsibility with letting the people who need to know my past know.
For example, in the church setting, I told my Conference. I told them them because they are the equivalent of Bishops and the ones who ordains me. They also need to know to weigh the outcome of any possible ramifications if a local church member were to find out and complain, my "higher ups" will already know and had already accepted my gender presentation.
I am a female, through and through. My past will not harm my congregation members. If they were to find out and disagree with it, they simply find another church to call home. This is where I believe there is a difference with lovers. For me, not telling a lover may harm him. It is a strong emotional betrayal and not easy to just walk away from when someone shared their most intimate and vulnerable moments with you.
Likewise, with my congregation, they know where I stand with LGBT issues. They know I embrace everyone who walks through our doors. So, me not telling them of my past isn't really me trying to avoid controversy. It's me not having to desire to disclose the specifics of my sex. Me being a female, a pluralistic church, has no bearing on my ability to minister.
My professor is also right about another thing. If a discussion looks like it may head towards an encounter in which I may need to fabricate, I simply change the subject or not involve myself with any unnecessary disclosure.
It is an interest issue.
This winter, I need to spend three weeks in an Amish Community. I will dress like them, I will live them, I will work alongside them and worship with them. While they will know I am not Amish and I am doing this for a requirement in Seminary, they will never know my birth Gender. I just cannot. If I did, I would not be welcomed. These are times when I need to avoid certain discussions so I will not have the need to fabricate.
In the end, the issue isn't a low self esteem issue. Nor is it an issue of me being ashamed of being transgender or my sexuality. It is more along the lines that I need to protect my interests, job safety, and those who have confided within me.