Difficult decisions should be the easiest to make. This may sound counterintuitive at first but it's generally true.
Take for example a decision between hitting yourself in the head with a hammer and eating an ice cream cone. The decision is very easy because one is unpleasant and the other is pleasant so there's nothing to think about there. Now, let's say you're trying to decide between two favorite dishes on a restaurant menu. You might sit there thinking for a long time do I want this or do I want that? I think a lot of people will be familiar with the difficulty as the server comes back to your table and you're still not 100% sure which one to go with.
In this case the difficulty is because you want two things equally but can only get one. All of the items on the menu that you don't want that much aren't even in consideration at this point. So whichever of those two items you pick wont end up being a very bad decision you want both of them the same. Therefore it's unlikely that you're going to choose one and then realize it was a big mistake.
This phenomenon can be intensified when making a larger purchase for instance which car to buy. You know a sports car is not the right choice for you because you need to drive the family around, so maybe you're deciding between a van and an SUV, or between two manufacturers of SUVs, then you have to take and consideration the mileage, the amount of cup holders in the car, how much leg room there is, how much resale value that might be, etc.
If the stakes seemed high that you had to make a decision before the server came, they're going to be much higher now that thousands of dollars are on the line and you're going to be using this car for years to come. But again The same logic still applies. If you're having a really tough decision between two different vehicles to buy, it's because they're so close that whichever one you buy won't be a huge mistake. Maybe you'll get one that was slightly worse than the other thing you were thinking of but the difference would be so imperceptible at that point it doesn't even matter. Next time you are struggling, don't spend too much time worrying about it, just pick one. Use a coin if you need, or just choose the one that comes first alphabetically.
There is another phenomenon called analysis paralysis. This happens especially when you are faced with a large amount of decisions and become overwhelmed. A study found that if a grocery store carries a large variety of mustard brands, compared to just a few, the store with the wider selection will actually sell less mustard. Presumably people see 15 brands of mustard and can't decide which one they want and just move on without buying any. Again, in these situations, just grab one and move on with your day.