Claire, you are certainly not on your own, I have known I was trans all my life and didn't transition for a number of different reasons. First I thought I could be a man if I tried hard enough which sort of worked until I got pressure to find a partner. Next I had family to support, and in my case I was a single parent, so I really didn't have time for transition. Then my current soon to be ex wife said she could tolerate me being me at home, but going outside or on hormones was off limits. I have to say I really enjoyed this phase of my life as my dysphoria was under control, I had a dream job and my wife and I were having amazing adventures. All up this lasted 'til I was 65, with that last phase lasting 20 years.
Even when my dysphoria took over I didn't want to lose my former life, and I still cry wishing I could go back. I had to face that prospect of losing everything, and it really freaked me. That risk of loss is a legitimate reason to try not to transition. To put this into perspective, I would have gladly given my life for my wife and children (and now grand kids) so how could I risk losing them for something as uncertain as transitioning. Yes, I am a reluctant transitioner, all my life I chose not to transition, and even when I was told my life was on the line I said no. My fears were thankfully not realised and I have kept my loved ones, but not without putting them through pain, and that alone was reason for me not to transition. So I certainly understand why people would choose not to transition while you have a choice.