(Longest record of continuous insomnia for one year here. =w=/ )
1. Exercise (30 min, 3 times a week. Most would suggest aerobic types like running, but 2xAerobic & 1xWeighted would do you better in the long run. Google "7 Minutes Workouts" and "Bodyweight Exercises" if you don't wanna go out or get scammed by gym memberships.)
2. Yes, if you're always indoor, go out. Cabin Fever isn't just a bad movie.
3. Don't sleep later than 11pm. And stop yourself from computer/heavy exercise/food/water after 10pm.
4. Find a way to "turn your brain off" if you're thinking too much about "bad" things. (eg. For me right now Headphone+Bradio for 2 hours works wonders, but find your own thing that works.)
5. Probably not part of your problem as it seems emotion-based? but you might want to check if you have Sleep Apena as well? Especially if you're overweight or your relatives have that.
6. How important do you think sleeping is to you right now? If its not a high priority for you, well, nobody can help you there. v=3=v But if it is, then maybe it is worth enough to change your other schedule to fit it better. (Sometimes the change of mindset might be the most important thing, sometimes.)
As someone who's working in the mental health service, I'd say not everything need the mental health service... Then again I'm a guy in front of a computer, there's no way I can give accurate estimate here nomatter what you say, so... If you thinks there's a need, then that can be a thing you can do too.