OP, you're approaching investing with a different mindset than that of most MMM folks.
Generally speaking, we believe in buy and hold, for decades, and not selling until you actually need the $$ to spend on living. Buy low-cost index funds, for maximum diversification. So you set a comfortable asset allocation, jump in the market, and do your best to ignore its daily, monthly, and yearly ups and downs, trusting that over a span of decades, things will smooth out and you'll be fine. The less you mess with your investments, the longer you just forget about them, the better off you are. You maybe rebalance now and then to keep your AA, but that's it.
We lost 1/3 to 1/2 of our investments in 2008. We held fast. Now they've recovered and then some.
We lost probably 1/4 of our home value in 2009. We didn't sell. It has nearly doubled in value since then.
Yes, crashes will happen. Recessions will happen. So you plan for those too, set your AA accordingly. Maybe when you go through a recession, you'll realize you're not comfortable with your AA, so you tweak it a bit so you can sleep at night. But then you forget it again and go back to living your life. Because historically, invariably, recoveries happen too; they just don't get as much press. More days are new all-time highs than you might realize.
It's about the long game. If you approach the market like a mayfly, darting around, expecting to hang out for a single day, you're going to mess yourself up. If you approach it like a tree, where you barely notice the seasons, let alone the years, you'll realize that who's president doesn't matter, because presidents change every 4-8 years, and you're in it for many multiples of that.
It's hard to make that mental shift. But that's how you get to FIRE.