Since An has made his decision regrading the letter, I will not give detailed comments and/or provide an edited version.
However, please be aware that this letter [updaded Dec 13] is in no way qualified as a letter of recommendations.
1. It is overly sentimental. Most judgments are based on feelings, rather than objective assessment.
2. Never is there a teacher who equates himself to being a "comrade" of the student.
3. A teacher never says he is "proud" to be a teacher of a student, unless the student has accomplished ultra extraordinary results in a particular situation, or in a very personal, private circumstances.
Bottom line: The writing needs not to be perfect, but it has to make psychological sense. If you write the letter of recommendation for yourself, you have to be able to take a distance from yourself and evaluate your qualifications objectively, without any passion. Otherwise, ask someone else to help.
Best of luck.