Being stressed out constantly causes your mind to race with thoughts and not allow it to shut down properly at night to allow you to sleep.
You'll need to do your best to reduce the stress that's keeping you awake and also may need to take sleep aids to get to sleep if the stress is not allowing you to sleep.
A natural sleep aid is to take a tablespoon of apple cider vinegar before bed. It works great for me when I'm having trouble sleeping.
You can also try taking some over the counter sleep aids if the apple cider vinegar isn't working for you.