You need to define how and what you are trading. You are way too loose.
I am assuming we are not talking Investing,and we are not talking a diversified portfolio..
For this discussion,are we in agreement that you are trading a single asset,or a very concentrated portfolio of 5 stocks or less?? 10 stock plus portfolios are a different ballgame...
Your hypothetical example is a single stock,so lets stick to that.
My answer would be exactly as you suggested,one MUST mitigate losses early,or should I say maintain discipline and adhere to the chosen reward to risk ratio,i.e 2-1 ,3-1 with a 10 percent max Stop....
I fully get that simulations may demonstrate stops are "hazardous" to ones P and L (bull market life preserver), but a 50 percent drawdown is an unmitigated disaster,and where you are struggling is there is a very good chance that a 50% drawdown doesnt retrace and turns into a 75% drawdown(game over) and i didnt account for survivorship bias..
It appears you arent a directional trader,and definetly not a short vol guy