Totally agree, I bought my first bitcoin mid-2011 and had severe FOMO as it increased in value almost 50% by the time I found out until I got my money to the exchange. I tested it with small amounts at first until I was confident in the technology. It later dropped in value by 95%. By then, I was more convinced than ever and was increasing my exposure at around $2 per coin (from memory).
I did not go all in (and would still not advise doing so). Instead, I invested what I was prepared to lose and around the amount I would generally put into a single stock in my portfolio.
I have sold and spent along the way (but again only small proportions of my holdings), but bitcoin (and now other cryptos) completely eclipse the value of my share portfolio now.
So, I guess it takes guts, but diversifying also helps, not my not going all in when I first heard, allowed me to spend more of my dry powder when the prices fell.