You can travel light and carry all you need for long term wilderness living/survival, all that is accept perhaps enough water and food! If there are water holes on your route then there is no problem. If you are able to hunt & forage on the way then there is no problem. But what if you get diverted have to by-pass those water holes? What if you are trekking in winter and there are few edible plants to find and the game is scarce? Then you have a problem. You can survive for three days without water, but this also depends on how hard you are working. You can survive three weeks without food, but again, this is dependent on your exertion level. You probably know as well as I that when you are working hard your need for water and food increases. You are drinking all the time to stay hydrated and come lunch time you are very hungry. To go without water and food is dangerous, because the lack of water and food effects how you perform, mentally and physically. One minute you think you are doing fine, the next minute you are feeling sick. Keep going and you will collapse.
Sharing the load with a partner is fine, you can carry the shelter, kettle, arms and ammunition, your partner can carry the water. But water is heavy, and to be safe and practicle your partner also needs to carry at least some of her/his own equipment. Simply put, you can never really carry enough water for a long trek unless you can find a water source along the way to refill your water bottles. Even then to be safe you will need to stop and boil that water before you can drink it.
So what is a simple and practicle alternative? Using a trekking trolley. A trekking trolley can carry a lot of weight, and there is a wide variety of different trolleys to suit your needs. On a level surface pulling a trolley is easier that carrying a heavy load, but going uphill you will need to pace yourself. Even so, when you stop for a rest on the trail and take a drink of water, you are not still bearing that load. If you are travelling with a partner or a group, you can use a rope to link you to another trekker who can help pull the load up steep inclines. If you can afford it, you can purchase a trekking trolley, if you don't have the funds, then you can make your own without too much trouble.
An Australian made trekking trolley.
A trekking trolley that the author made from old wheelbarrow parts and bush timber. This one only has one wheel, but the author plans to make another one from an old golf trolley.
When you reach your destination this trolley will still be of use, and can be used for: transporting game, transporting water from a water source, carrying firewood, transporting rocks for a fireplace, moving camp if needs be. Perhaps you can think of further uses?