בעזרת השם יתברך-יום ג פ ויחי, י טבת שנת תשע"ט
Lekuvid my dear...... Talmid yeshivas Tiferes Hatorsh Breslev
I received your letter.
I'm happy to hear that your life changed for the better since you came into the yeshiva, you write that you received a new heart, and that from now you strive only to do good. This is exactly what happens when someone becomes מקורב to the rebbe, the holy rebbe takes his 'לב האבן' literally meaning heart of stone, and instead gives him a 'לב בשר' a good heart. As it says (yechezkel 36, 26) ונתתי לכם לב חדש ורוח חדשה אתן בקרבכם, והסרתי את 'לב האבן' מבשרכם ונתתי לכם 'לב בשר' " 'לב בשר' are the same letters as ברסל"ב (chai maharan siman 339).
Continue learning mishnayos every day and try to say חי פרקים, mishnayos had the power to eradicate the bad in a person and cleanse his soul. Mishnayos even has the power to save a person who has fallen into a deep pit of aveiros. Maharosh would say the acronym for 'העלית מן שאול נפשי' is משנה - simply meaning that when a person says mishnayos he is taken out of שאול תחתית.
I'm very happy to hear you have crawled out of your depression and you try extremely hard to be happy. The holy rebbe says (likutei maharan chelek 2, siman 25) "מצוה גדולה להיות בשמחה תמיד" it is a great mitzvah to always be happy, "ולהתגבר להרחיק העצבות והמרה שחרה בכל כוחו" and to try your utmost to get rid of your depression and misery, "וכל החולאת הבאין על האדם, כלם באין רק מקלקול השמחה" all disease and sicknesses that afflict a person only come from depression and sadness. The rebbe says further "וגם חכמי הרופאים האריכו בזה, שכל החולאת הבאין על האדם, כלם באין רק מקלקול השמחה", even the doctors admit that all problems and sicknesses, result from not being happy, and simcha is a cure for everything. When a person is happy he relieves himself from all pain and suffering.
Regarding to that you feel unwanted and not important here in yeshiva; you should know this is just another tactic of the yetzer hora to demoralize a person and take him away from the tzaddik. He does it to everyone that wants to be מקורב to the rebbe.
Let me tell you a story that will give you great chizuk. When R' Yidel became close to the rebbe, people came to tell him that the rebbe is angry at him. R' Yidel did not know that this is all the yetzer horas doings, that the yetzer hora will try everything in the world to distance a person from the tzaddik. He was hesitant to go to the rebbe and ask him what is really going on. After 3 days like this, he couldn't bear not seeing the rebbe and thought to himself 'whatever will be will be, but I have to go see the rebbe'. The rebbe understood with ruach hakodesh what R' Yidel was going through, and when R' Yidel stepped into the rebbe's room the rebbe remarked "when a person comes to a place of שקר, אמת tries to win him over, but if the person stands strong and doesn't waver in the face of שקר, then 'שקר' turns to 'קשר'. The rebbe then concluded "you will now be connected to me your entire life".
You can see from this story how hard the yetzer hora tries to confuse a person with negative feelings and thoughts, his only goal is, that the person should leave the rebbe. Therefore one must daven and stay strong that שקר should become a קשר של קימא - an everlasting bond to the holy rebbe.