Well ya started out wrong and ya never got better.
Some things I do know from past military experience, law enforcement experience and the fact that we’ve kept this ranch operating for over 120 years. Oh and by the way I am not a prepper but I do find many very naïve and amusing. As far as losing money on an investment, try being in the oil and gas business as long as I have.
1. Organization. No matter what you have prepared for if you don't have a way to protect it from an angry crowd you might as well give it all away and put a bullet behind your ear.
2. Help. You need a plan and people to help you implement it. You need someone to watch while you sleep. Animals can be good help for security. Get a big, noisy dog. A loud low pitched bark can scare a lot of people away.
3. Fuel. If you can't stay warm or keep frozen foods frozen then you have a lot of waste. You need fuel to run a generator or solar collectors to keep some communications going, charge a phone, charge a radio, run a TV, radio or whatever. You need oil for lamps, candles and a way to light them
4. Weapons. If you can't defend what you have just give it away. Plenty of ammo. You may never fire a shot, but you might be able to trade a little ammo for a lot of food.
5. Water. Most people don't have enough water to last more than a day. People buy lots of 2 liter soft drinks that make great water storage but people don't do that they just throw the bottles away. You need a way to board up your windows so people can't easily knock through one and enter your place.
6. Food. You have to eat and if the problem lasts a long time you will need stuff to trade, food is one of the best things to trade with. Frozen foods are only worth having if you have a means to keep them frozen, that means running a generator at least a few hours a day. Generators make a lot of noise and alert everybody you have supplies.
7. Silver coin. Pre 1964 American silver coin will be one of the only real monies worth having. Silver dimes are easily cut into halves so dimes are a great item to store.
If you are in an urban area it will be tough. If you can get 25 miles or so away from a major city you will be a lot better off. Without gasoline foragers won't be traveling too far, most people aren't used to walking and can't go very far very quickly especially carrying everything they own.
None of the items above just happen, you have to plan for it in advance. It is best to do it over a period of years, we may not have that period of years now.
The things listed are hardly even a start but if you don't have them you might as well go to a government shelter and starve there.
Once society falls apart it will come back. It may take weeks, months or perhaps years but eventually life will find some kind of normal.
Most people deny that these things can happen and hopefully they never will but it is senseless to not prepare for the possibility.