Say you needed to untangle a ball of string, but just as you began, you inadvertently dropped it into the kitchen sink, which was full of sudsy water; then the lightbulb went, plunging the room into complete darkness. Now rather than trying to solve all three problems simultaneously, the answer is almost certainly to uncouple and prioritise. Dry your hands. Fix the light. Take the string out of the water and probably allow it to dry, too. Then - and only then - have a go at untangling it.
It seems pretty obvious to tackle a hypothetical situation in this way, so why do we often fail to follow similar principles when we've multiple issues occupying our minds? Why do we believe we can solve them all at once? Why do we persist in believing that they're all connected somehow? It's easy to assume, because everything's not as it should be in one part of our life, that the same reasons affect other areas. This isn't necessarily the case, though. When you've multiple worries, it's not always easy to uncouple one from another, but doing so is almost certainly the best way to move forward. One step at a time.