Hello, since the symptoms have been present since 15years, you might require to be on medications for anxiety/depression after thorough assessment by a psychiatrist. If you have not consulted one yet, you must do so.
Next Steps
In the meanwhile, you can follow steps of good sleep hygiene and include exercise in your daily routine.
Health Tips
Insomnia is usually accompanied by anxiety and/or depression. A psychiatrist will be able to help you understand these better.