Wow, I cannot believe I didn't see this thread earlier, especially with so many replies.
I personally detransitioned and know many others who have too. The HBSOC (Harry Benjamin Standards of Care) which was the primary method of gatekeeping back when I transitioned in the late 90's, was and still acts as a godsend. Without it I might very well have made a major mistake.
I lived full time, had a job, dated, and was going to school and I was very happy with my female role. However, I couldn't get past the nagging doubts that all this was in my head. Regardless of the fact that my brain was telling me "I'm a girl, I'm a girl, this is right, being male was wrong" I felt like my brain, like with so many other conditions of the mind, could have been lying to me. I also hated the lying and deceit that went with transition to maintain stealth - modifying the experiences of my past constantly, never feeling like I could honest or real with anyone. I thought "damn I went to all this trouble to 'be myself' and I cannot even be honest now! I'm still a in a box!"
Well I got sick of the box and the lies and starting 'coming out' that I was transgendered. For some reason, having people know of my past made me feel more at ease - a lot more at ease but it caused problems of its own. Dating prospects were more difficult obviously and some of the people I knew who were cool with the female me, couldn't handle that the person they thought was always female wasn't.
The final thing that kicked me into going back, to detransitioning was seeing all of the incredibly disappointed and unhappy people who were transitioned. Im not talk about on the forums, but in real life. After all they did, they still regretted, still bemoaning things they were missing in their lives and those sadnesses were consuming them. Those who didn't pass at all were even more depressed and I had to deal with a number of other TG people I knew committing suicide. I started to think "there has to be another way! Not everyone can have a successful transition, and those who do seem to have the potential for intense lingering sadness".
So I decided, even though I might be one of the lucky ones who transitioned at 19, could pass easily and quickly, I realized I wanted to see if I could make it as a guy again, so long as I was "out", didn't live in the box of being male, and tried cognitive behavioral therapy techniques to control the triggers that provoked my GID. After all, if it didn't work, I could always go back right?
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Let me mention about something Kate said. Kate said that the RLE, as annoying as it is to many transpeople, is very important for weeding out those who could otherwise live without transition. I echo that so strongly it moves me to tears. The detransition group I am a part of has VERY strict confidentiality rules - for one to protect their identities, and two to protect them from members of the trans community who don't want to hear about them, but I will tell you this.
Nearly every post op I've met who detransitioned only got into the mess they did because they DIDN'T follow the the proper order set out by the SOC or WPATH. Sure, roll your damned eyes at me you doubters and naysayers and "I should be able to whatever I want"ers, but I'm serious - gravely serious. These people were the same way, they were convinced they would DIE without transition, they never thought for a moment they'd regret any part of it, afterall, their whole lives they wanted it. They listened to people who said the RLE was dumb and gatekeepers were annoying, and justified hurrying the process. They also cite pressure from other TS's to transition, transition, transition - which all of us can attest exists from our community even if it isn't direct, it is always indirectly there. Finally they cite they never knew there was another way to do it to live with GID without transition. These people are generally very sad pandas. In their shoes I probably would have remained transitioned, but I cannot be sure, but they exist, and they deal with challenges many of us couldn't dream of.
In fine I'd like to say that even if you have no doubts when you begin transition, don't believe for a moment you'll never change, don't cut corners on the SOC, don't think you are better or more "trans" than others. These attitudes can blind you to the reality of the possibility that you *might change your mind as remote or impossible as that may be, and then it will be you I get to read about - you who wished things were different, that you had stopped earlier, that wished you had taken more precautions.
I hope you can see why I don't really like seeing gender-questioning individuals being pushed into transition's path. The truth is MOST MOST MOST of the people I know who have regretted it and are post op... wait for it... transitioned YOUNG (before 30). In the end, people change, and they change A LOT in their 20s. Take that as a warning you whipper snappers.