Maybe because you haven't been able to discipline yourself on this, or "learn" better (like someone suggested) or even remember, perhaps... that this is what you have to do...and to quit thinking you can decide a good solution.
Medicines make ppl feel better, and often OFTEN patients quit taking them, forgetting that it's the very thing making them feel like they don't need them!
I hope you will be able to get back on a good program of medicating ... and know that you are worth it... worth the time to take them, worth their cost, and worth the good feeling while on them!