Medication alone is usually not effective in cases like this. You can trace the start of the depression to a particular event. It’s likely that the sleep disorder is making things worse. You need to talk to a therapist who can help you make sense of what has happened and who can give you needed support while you recover.
I understand that you are wary of talking to a therapist. But that’s exactly what you have to do. You’ve written an articulate letter about how you are feeling and your concerns about therapy. I suggest that you make an appointment and take a copy of your letter and this response with you to your first meeting. Give it to the therapist. It will immediately provide him or her with important information about how you are feeling and your worries about treatment. And, please, if the first visit doesn’t go well, don’t judge all therapy as being unhelpful. Sometimes it takes interviewing several therapists before a person finds someone they feel they can trust.
I wish you well.