The first thing you should ask yourself is what is under my control and what do I need to accept. You cannot control your insomnia but you can control your exposure to light. You cannot control the stress in your life but there are practices to help you relax and let the ideas go.
Insomnia can be caused from stress which you will experience from time to time. This is usually transient or temporary. It usually lasts less than 2 weeks and there are a few tools that will help you move past insomnia.
One of the main causes of insomnia is financial stress. Money will always be a problem. People will always need more money. There are good programs out there to get your money straight. Dave Ramsey offers software for free. Better Budgeting has an excellent newsletter they put out once a month. Tony Robins has a new book about finance and managing money.
If it is other stress you can find simple ways to distress. The 8/8/10 breathing exercise works for some. For others progressive relaxation works, still others find that meditation works. Even if you just take time to take 10 slow deep breathes; this will increase you oxygen level and decrease your heart rate. How much healthier and more relaxed would bedtime feel if you were able to let go of that one last nagging issue.
Your environment can also contribute to your insomnia. Is it that the clutter around you keeping you awake? A room with clutter, or your computer and work can keep you focused on what needs to be done rather than sleep. Taking time to declutter will help you significantly to relax and enjoy the experience. The same is true of the bedding. Sheets and blankets matter and should be comfortable. The room should be dark and cool.
My final suggestion is to have a pad and paper next to the bed. Not your phone or tablet. This will allow you to write whatever you feel needs to get done and will let you let it go because you know you will remember it in the morning. The action of writing