The tone of your letter suggests that you might have depression. A key phrase in your letter is “I feel like.” Feeling like something is true does not mean that it is true, especially if you have depression. Cognitively, depression creates distortions. Those with depression often view their lives through the lens of negativity. They have a tendency to minimize positive aspects of their lives while maximizing the negative.
Individuals who are depressed also perceive others as being much happier than they really are. They assume that everyone else is happy and flourishing, They assume that they are the only ones who are unhappy, since obviously everyone looks happy. For some, it becomes the proof that they are a “loser” which ultimately serves to fuel their depression. However, when we look at others we need to remember that we can only see the outside. Most people carefully control the “outside” that is public and manipulate that appearance to give the best possible impression. Simply put, they hide their doubts and fears and often their true feelings.
You said that your parents “don’t believe” in therapy but they might change their mind if they were made aware of your possible depression. If you feel uncomfortable speaking to your parents, consult the school guidance counselor. Detail your struggles and concerns. Tell the guidance counselor about your belief that your parents won’t take you to a psychotherapist. Perhaps he or she could speak to your parents. Hearing that you need help, from a third party, might motivate your parents to take your concerns seriously and to assist you in receiving professional help. Many people receive effective treatment for depression and live happy lives. You can too but it may require you being your own mental health advocate. Please take care.