Can developing good habits kill the bad one's?
The short answer - Yes.
The long answer, well it is a long process and it takes time. But developing certain good habits are known to kill bad habits. Let me give you an example from my own life. 6 years ago, I was a sedentary, lethargic and utterly unfit person. I used to eat all kinds of junk food, smoke almost 8–10 cigarettes a day, sleep late and wake up late. All my vital health parameters like BMI, Blood Pressure, Lipid Profile, Urea, etc had gone over the roof. I knew that all that I used to do like smoking, binge eating, oversleeping etc are bad habits. But I did not know how to get rid of them. In fact, I never tried to shed those habits because I used to enjoy them.
In 2011, I took up running to control my weight. It was a difficult process. It took me several months and a truckload of will power to get into the groove of running. You can read that story here: Couch Potato to Runner - My Story!
In about an years time, the running habit was firmly established. I started calling myself a runner. I did not know that I was setting up a habit that would change my life. I lost the extra weight that I was carrying for most of my life. The health parameters came back to normal. I started taking part in longer runs. This meant I has to eat healthy food. My binge eating stopped. I had to wake up early to go for my daily run. This meant that I had to go to sleep early. My overall lifestyle changed because of the habit of running. In order to run better, I felt like quitting smoking. One fine day, I just stopped. The runs were much more enjoyable and I became faster.
Today, I am a changed person. I have become much disciplined and have incorporated many other practices into my daily life. My life today is 360 degree different from what it was 6 years ago.
So, yes, it is possible. It will take time. But with your will power and patience, a good habit will help you kill bad habits. Such habits are known as key-stone habits. They are the ones that help add more and more good habits in your life and drop the bad ones. Example of keystone habits are running, meditation, tracking your food intake, maintaining a daily to-do list etc.