hoolihttp://www.sexchangeregret.com/
1. not nearly every trans person gets sexual reassignment surgery so this isn't universal in that regard
2. you cannot divorce the percentage of people who feel 'regret' because they were actually wrong about what they wanted their genitalia to be from the percentage of people who feel 'regret' because they've been taught their whole lives that they're wrong for wanting to be a different gender and have been depressed and self-loathing for years before their surgery
3. example of the above: http://www.advocate.com/commentary/2015/11/02/firsthand-account-torture-conversion-therapy
4. there are also many people who claim to be "ex-gay" because they've also had bullshit crises of conscience due to their upbringings/societal pressure, I fail to see the distinction