Dear [Name],
I am writing this letter to apologize for the discouragement I have caused you. I know that my words and actions have had a negative impact on your life and I regret that immensely.
I want to take this opportunity to explain why I acted the way I did. I was feeling overwhelmed and stressed out by the situation and I was not in the right frame of mind to think clearly. I was not considering the consequences of my words and actions and I realize now that I should have taken a step back and thought more carefully about how my words and actions were affecting you.
I am truly sorry for the hurt and discouragement that I caused you. I understand that my words and actions have had a lasting impact on your life and I want to make it up to you. I am willing to do whatever it takes to make it up to you, whether that means spending more time with you or helping you in any way I can.
I hope that you can forgive me for my mistake and that we can move forward. I want to be a better friend and supporter to you and I will do my best to make sure that I am always there for you.
Once again, I apologize for any pain or upset I have caused you. I hope that you can find it in your heart to forgive me.
Sincerely,
[Your Name]