We often find ourselves tending to fall into the same sins over and over. Each one has his own particular weakness that he has to face up to and work to overcome his whole life long. It might be pride, anger, sensuality, laziness, etc. We are right in feeling that we are unworthy to carry the Apostles torch when we sin. What we sometimes dont realize is that we are unworthy even when we dont sin.

Now, you ask me how to overcome this feeling. Frankly, I dont think you should try to overcome it. This is more than a mere feeling; it is a reflection of your conscience. You dont feel good because you know something is wrong, or at least not as good as it should be.  

So, instead of trying not to feel that way, what you need to focus on is overcoming the habit of falling into the same sin all the time. This will take patience, prayer, self-mastery, effort to avoid the occasions, regular confession (even if you havent committed the sin) and regular examination of conscience. Your spiritual director will help you map out the best way to work on these and other helpful points.

As regards feeling unworthy, it will be important to cultivate this conviction, especially when you start making progress in overcoming your sin. Why? Because we are never worthy of the priesthood, we cannot be faithful to God on our own strength, and we are terribly exposed to being proud and wanting to be served rather than to serve. Feeling unworthy will help us live with the conviction that we are priests because Christ has chosen and called us, and if we are going to be faithful we need to build our lives on prayer, sacrifice, humility, avoiding the occasion of sin, and bearing as much fruit as possible in our daily lives.