It is a sad but true fact that it's difficult to do anything by yourself. You first need the motivation to not just slump down with the sheer weight of everything that needs to be done; a friend, a lover, or a dependent start to make you realise that there is something more beyond yourself. As I have mentioned before, it doesn't take much extra to do things for two than for one - particularly if that other is doing plenty of other things, too. Add a third, a fourth, and things become much easier still - everyone can start to pay attention to only a few things, because others are doing the rest.
Take, for example, what I am trying to do.
It is simple in and of itself - a hobby farm with some extra survival features. A small number of growing food trees that need to be watered every few days; the accumulation of resources and knowledge; working towards getting a bug-out shelter for emergency use; then, the bits required to keep a hobby farm going, the additional work beyond just watering - mowing, weeding, fertilising. Other options also become necessary once one thinks about longer term survival - a forge, a workshop, a chemistry workshop, some form of amateur radio set-up. Chickens, maybe geese, perhaps goats - hard to get and keep, but harder to get once things have degenerated and you are limited to what you have at hand. Wood has to be gotten, chopped for the stove (if you have a wood stove). Repairs have to be made on equipment.
A moment here for a few asides, though. Some might question the need for a chemistry laboratory; there are far, far too many useful things that we have grown to expect that may not be easily obtained - especially if everyone wants them, and no-one is producing. Expect general anaethestic? It is difficult, but possible for someone with a reasonable amount of training to produce ether from ethanol (purified grain alcohol) and sulfuric acid (of a reasonable quality). How do you produce alcohol? A still is easy enough. How do you get sulfuric acid? Car batteries have many nasty things in them, and are barely suitable - but a chemist (as in chemistry, not pharmacy) would be able to create it - and with some geology know how to get the raw materials. Likewise, nitric acid is a very useful thing, difficult enough to get in some places, but important for some industrial applications. Let us not even start to talk about more... combustible applications.
The important thing is - there are far too many useful (in a necessary, survival sense) things that we take for granted, and only a limited supply. You simply can't depend on "finding" (finding, trading, or otherwise) essential supplies when you need them most, you need to have the ability to make it, or trade something else for it - and essential supplies are difficult to trade for when using them means using them up.
I write this after seeing my father's notes scribbled along the margins of "The Earth Abides" - notes about chemistry, geology, hobby farming. I flick through the book, find my father's writing growing more strained, obviously written over a long time, the last page the only with a date - a few days before he went into hospital.
The upshot of which is the fact that a lot would need to be done, and the more hands that can help, the better. But they'd better be working to a common goal.