Don't bother with it in the early game when you're leveling up quickly and haven't earned any money yet. Keeping equipment in tip-top shape is optional. After all, you did sign up for a challenge, so why shy away from it?
If you're playing on Very Hard and don't take care of your stuff, it'll hurt, but it's still doable. You do lose some damage (how much depends on the difficulty level, I know it's barely 10% or so on Normal), but I bet most people don't bother optimizing their damage with oils and potions most of the time, anyway. I fight with fast attacks primarily, so it's happened a couple times. Weapons don't break, I've continued using them at 0% when I'm out exploring and run out of repair kits. I understand the compulsion - we have been trained by many games to always want equipment to be fully repaired - but if you can just control your anxiety over it, it's not that big of a deal.
You do not have to keep your swords repaired, they are usable and still effective no matter their durability status. I think some of the problem is most people are not observing exactly what it means to have your equipment degrade, and may be applying bias formed from other, far more annoying implementations of this sort of mechanic.
