People talk about not losing money until you sell, but it's a double edged sword. That same logic implies that you haven't gained any money until you liquidate your position either. Honestly the best way to look at it is that when the price goes up, you make money... and when the price goes down, you lose money. Your gains/losses can change constantly, but selling will cause that to stop, effectively locking in whatever gains or losses you have.

Just because you plan to wait a long time before selling bitcoin doesn't mean you have not lost money over the past month or so. Everyone who owns bitcoin has been losing money recently.