A reasonable caution to consider. After we have been out for a few years, many of us will know of folks like your former friend. Unless lack of gender congruence is the one and only problem in our lives then we, like everyone else, will have a full range of challenges and relationships to mange.
Jealousy and anger are emotions that any of us can feel but, if they dominate our lives, no amount of fixing other things like our appearance will likely suffice or satisfy. Saying that, many of us have found ourselves far better equipped to deal with life's demands when our gender dysphoria is reduced and our identity feels real.
Fortunately, for many of us, this is a slow moving process with multiple hurdles and obstacles to encounter and time to fully consider our course of action and results. What a great and interesting journey we take!