This got me thinking, is there others like him who kept wishing till now or might forever wished they had never sold their Bitcoin when they had handful of it? What is the solution to let go of the regrets?
Many holders who did not understand the true value of Bitcoin ended up like your friend. They may have never imagined the valuation of Bitcoin and its high future value. Some may have had Bitcoin but sold it for an emergency or some did not hold it despite having the opportunity to do so. We need to be more thoughtful about the future and arrange the economic infrastructure with Bitcoin holding.
I see the only solution to this by doing DCA because the strategy of accumulating Bitcoin in this way is a part of disposable income. Along with your family's daily needs Bitcoin accumulation and long-term cycles. By deposit Bitcoin in this way investors will not have to regret it in the future because Bitcoin is a part of discretionary income without any decrease in their real assets, which they could have kept in the account of unnecessary expenses.