I have a hard time falling asleep, any ideas on what it could be and how to treat this?

The list is long: You need to see a sleep specialist. The list on causes is quite long. Some items include depression, anxiety, medication side effect, delayed sleep phase (while trying to go to sleep at a time you're not ready to sleep, but just "because it's time"). Bottom line: see a sleep specialist and he/she can get a good history and likely help establish the reasons for this! good luck!