If you really believe in the relationship, don't give up when the going gets tough. And when I mean tough, I mean fighting and bickering and spats. If there's cheating and unfaithfullness, that is a different matter. But if its a matter of leaving a cap on or off toothpaste, you need to rethink your priorities.
And if there is a relationship you want to go after, go after it. You don't want to be nagged by what-ifs.