Long post - here goes...
I was doing a bit of reading on a site referenced by another member here, and read some material that caused me to re-think something that I had been taught and that I myself have preached. Not by chance, a trusted evangelist friend of mine preached on the very same topic less than 24 hours after I had read that article. He did a little better job explaining the concept, but I'm much closer to understanding and accepting a deviation in how I perceive the subject of law vs. grace.
As of a certain time frame growing up, I've always been critical - of myself and of other people. Intensely critical. Guess I fit in as a "fundy" then, eh? But I think my critical spirit is sourced in my rejection of my own gender perception. I've always wanted to live by a set of rules, and I've always been critical of those who stepped outside of my perception of the rules, especially myself. If my person, my identity and feelings, did not conform to the rules of my biological gender, I was guilty of breaking God's rules somehow. And since I could never force my identity and feelings to conform to those "rules," I could never truly feel forgiven. Constant self-doubt, self-hatred, self-despising - and tending towards condemning others with a measure of that same self-condemnation! What a mess!
Fast-forward to the present. What I think I've been lacking is a true understanding of the Christian's position in regards to the OT Law in its entirety. The perspective I'm tending towards now is different than that which I've grown up with. As an individual who years ago trusted in Jesus Christ as my Lord and Savior in a spirit of humility and repentance, I am saved from my sins. I am no longer under the law - therefore what Paul says in I Cor. 10:23 (and 6:12) about all things being lawful for him applies to ME, too! That means I am not bound lawfully to obey Deut. 22:5. The OT Law no longer applies to me.
Does this open a can of worms? No, because a different standard now applies to me. While I am not bound to live by the OT Law (for every one who lives by any part of the law is bound to fulfill the ENTIRE law - hence the godhatesshrimp issue that tags along with Deut. 22:5), I am bound by the law of Christ.
What is this law of Christ? Same passage in I Cor - expediency and edification. Every thought or action must be put to the test - not a test of the law - but of whether or not this thought or action will draw me closer to Christ or will help me in pointing others to Christ (including spouse, children, church family, community, etc.). The question must be asked whether this thought or action will encourage others in their walk with Christ.
Application time. What are my goals in relation to my walk with Christ, my family, my congregation, and where does my gender identity fit in? Will transitioning edify, or will it confuse? Ugh. I think I know the answer to that question.
Does that completely throw out the option of transition? Full transition - yes, I think so. Partial transition - is still an option. For example, today I finishing shaving hideous man-hair off my now-femininely sleek legs; I'm wearing clothes that I know are feminine, but if someone stopped by to chat with me, they wouldn't realize. While my gender frustration isn't gone, it's tempered slightly by me knowing that I've expressed my feminine core in a slight way. But my conscience knows that even if my kids walk into my office, they will not be confused by what daddy's wearing. How far I can go is yet to be determined by both me and my wife.
The Deuteronomy issue? Not an issue for two reasons. One, I'm not under the law so it does not apply. Two, I have a man's body and a woman's mind, so I either walk around naked (not an option, unless I'm trying to scare someone away) or I can choose which gender's clothing to wear at whichever time, limited by expediency and edification.
Wall of text ended. I've re-read this post several times to make sure I shared my heart clearly. The conclusion I've come to at this point does not completely fix the problem, but it is the most balanced and workable conclusion that I can find (again, at this point). If the dysphoria gets worse, I'm not sure what I'll do; but I don't have decide that yet. Thanks again, Sarah, for your encouraging words. If I lived closer to Wisconsin, I'd love to visit with you.