How do you know Bitcoin will recover?

Most people here say they know for sure that bitcoin will recover.

Looking to get some opinions on how you can stay so bullish when the price action seems bleak.

The main reason I'm asking is not because I disagree with that sentiment or don't believe in Bitcoin. I would actually like to start DCAing now that the market is undervalued to get a bigger return later. However my fiance is very hesitant on putting anything into Bitcoin as she sees it as on a downtrend dropping 53% since it's ATH and not slowing as of yet.

So I would just like to get some of your reasons or examples as to how you remain so optimistic in this situation and maybe I can use some of them to change my fiance's mind so we can be in a better financial position in the future.