Became a stepdad three years ago
Married my wife when her kids were 4 and 7. Biggest life change imaginable. Used to be pretty selfish with my time and now everything revolves around school schedules, soccer games, dentist appointments. Some days are insane and I miss just being able to do whatever on weekends. But man watching those kids grow up and knowing they depend on me for stuff, helping them with homework, being their person when they're upset - that's worth everything I gave up. Wouldn't change it now.
Three years in and you're still going? That's when a lot of guys tap out. The fact that you're thinking about how you've changed says a lot about your commitment to those kids.