Epictetus, in Discourses, wrote: "And since strong habit leads, and we are accustomed to employ desire and aversion only to things which are not within the power of our will, we ought to oppose to this habit a contrary habit...". If you want to break a bad habit, try doing something new or develop a new good habit that contradicts your bad habit.
Or better yet, try an approach that is the opposite of what you'd normally do. My favourite version of this Epictetus quote, featured in Ryan Holiday's and Stephen Hanselman's The Daily Stoic, is also the most straightforward:
"What assistance can we find in the fight against habit? Try the opposite!"
Things aren't going to get fixed if you try the same solutions over and over. Consider all approaches, even the opposite of what you initially thought was right. Sometimes the most counter-intuitive solution is the best answer to your problem.
Having a hard time falling asleep? Try what I call the "sleepover" approach. Remember when you were kids and you and your pals were determined to "stay up all night!" How'd that usually go? Stop trying so hard to sleep and try to stay awake instead. It shifts your focus off of your problem so you can finally relax and drift off.
Eat too much candy? Don't try to stop yourself from eating it, you'll just want it more. Eat as much as you possibly can until it makes you sick. Nobody wants to eat Skittles after violently puking up rainbows all night (trust me).
If you keep having bad dates with people who seem like your type, maybe try dating someone who seems totally wrong for you on paper. You might be surprised how much chemistry you can have with someone who has different interests and perspectives.
Perhaps opposites attract, after all?
Obviously, this isn't a good approach to fixing every problem. It's ok to trust your gut and stay the course most of the time. But if you're not getting anywhere with your traditional approaches, stop being so stubborn and at least consider the opposite tactic. Your intuition can sometimes be your own worst enemy.