Haven't seen my folks in years. Spouse dumped me because I practically didn't exist outside of work. Absolutely no hobbies or traveling in years. No guarantee the company will be anything but a massive drop in my financial history. You're constantly running out of money, so you're cutting every unnecessary expense, and you're living on scraps for years, knowing that you could be making 10x that much in the workforce. You can't quit though because so many people look up to you for direction, they need you to be there and lead them, to be certain of where you're going. The stress can be so high you just want to roll up in fetal in a corner and disappear. You understand why so many founders end their lives.
The experiences however and the connections are priceless. The feeling of playing the game on your terms is liberating and the hope of the upside is exhilarating, but I still wish the price wasn't so high. The amount of personal growth is astounding: once you go through the above, everything else feels like easy mode. You have to develop resilience, charisma, diplomacy, discipline and so many other traits or you will sink fast.
In hindsight, I don't know if I'd do anything differently. When you're this deep, you try not to dwell on hypotheticals.
I remember many years ago when I was sold to the startup lifestyle by the sexiness of the message, but the dozens of PG essays and stories of success and freedom. Nowadays I caution people to truly dig deep and understand if this is worth it to them, ask them if they're ready to sacrifice everything for likely nothing at all. Ultimately we're slaves of power law and similar to Hollywood talent in our outcomes: a very small fraction of us is going to becomes gods through either luck or huge sacrifice, and 99.9% of us will be waiting tables for the rest of our lives, or decide to do something else.