OP, I feel as though you have answered your own question. If you're trans, you're trans; you can't change that aspect of you any more than you can change your genetics. One day, they might make a pill that eliminates gender dysphoria completely, and sign me up if they do. Till then, this is our lot.
It seems as though you've tried to bargain with yourself on this matter for a long time, tried to compromise it, but it hasn't worked. In your mind, you seem pretty dead-set on transitioning. I, too, was my parents' only son, and the prognosis of transition was frightening enough for me to try and kill the desire for about 20 years. For 20 years, I proceeded to make terrible life decisions to try and convince everyone and myself that I was a man. I came out the other end successful, but after the demands of the daily grind calmed down to the point where it wasn't enough to keep me occupied, I knew it meant nothing.
You could work yourself to death as a distraction, you could try and shout over the inner voice as it gets louder with time, but eventually you hit a breaking point. Let it break. This is your dream. It's not necessarily a happy dream, most dreams get scary, but your conscience is pointing you down this path. There will be loss, there will be alienation, there will be no guarantees of anything. No one chooses to transition for the pension plan, but you can't live your entire life being guided by fear and guilt.
It's been an ugly, beautiful road so far. My family pretty much unanimously turned their backs, my job doesn't know what to do with me (I don't know what to do with it, either), lost a well-established long-term relationship, but I have hope and the conviction that what I'm doing is right. You're not just transitioning your gender expression, you're transitioning your entire life, taking the road less traveled. You can be afraid, but don't let it paralyze you.