"I feel burdened by my past conduct. It's hard for me to believe that Hashem will forgive me."
If we have not properly guarded our eyes in the past, we can change our behavior and Hashem will help us to improve our ways.
In fact, Hashem sent us an uplifting and encouraging message through the prophet Yechezkel: "Throw off all of your aveirot and make a new heart and a new spirit for yourselves." (Based on Yechezkel 18:30)
Rabbenu Yonah offers this illuminating encouragement:
If a person has acted improperly and wants to take shelter beneath the "Wings of the Shechinah"... I will show him the way to proceed. On the day that you lift your heart to return to Hashem, throw off all of your aveirot as if they never were. Consider yourself as a newborn child, having neither merit nor culpability. Today is the beginning of your actions. Today you will reflect on all of your ways... This outlook will facilitate your complete return to Hashem because you will be unburdened from the weight of all of your aveirot. Do not be hindered by thoughts that hold you back from returning to Hashem. You might feel, "How can I have the nerve to return to Hashem, after I acted so inappropriately so many times? How can I come before Hashem? I feel embarrassed, like a thief who was caught in the act of stealing. ... How can I observe His mitzvot?" Do not allow these negative thoughts to enter your heart! These feelings of despair are the influence of the yetzer hara. Rather, know that the arms of our Merciful Creator are always open to welcome those that return to Him. (Yesod HaTeshuvah)
Hashem releases us from the psychological barriers to repentance by urging us to throw off our misdeeds. In this way, He grants each one of us the opportunity to change our ways, regardless of our past conduct. He lets us renew ourselves and gives us a fresh start.
Today: Throw off the burden of your aveirot and start over. Hashem gives everyone another chance!