I understand how you feel cause just like you, I was selling my BTC's earlier and that was so regretting to see the market pump. I was not jealous but instead, I was happy for this amazing improvement. And I'd rather have to close my eyes and imagining what I should do when Bitcoin reaches $100k.
It is so much for that, whether we like it or not, we have to accept it even it is badly affecting our emotions. What we do now is to enjoy the moment, we can make an investment later once the prices drop again( that will be a long wait, I think).
Is it too late for you to get back in? Did you spent your money on something else? I had a friend who sold at 38k thinking that was the highest it will go (after it peaked at 41k and dropped to 29k and back to 38k) but then it became as high as 47k, he got back in at 42k and I think made all his lost back from that increase, now a bit equal but he got back in anyway. So even if you sold you could always get back in if you didn't spend the money already.
If you are dreaming about bitcoin reaching 100k and what you can do with it, it is still x2+ away from reaching 100k, so if you buy right now, and price reaches 100k you will double your money and even some more on top of that. I haven't sold thankfully, I am planning on maybe selling just a bit of it, but I am still keeping mine, I would suggest everyone to get back in and do the same if they want to, even if it goes lower, it will eventually recover and go up.