why can't I sleep

I've been going to bed stupid early, am sober, healthy, don't drink caffeine for at least 6 hours before bed, clean sheets, etc everything i can think of but my eyes still shoot open every hour at night and i sleep like shit and all I want is a full night of rest I don't want to take any sleeping pills because drugs are bad, I'd rather find a different way first so umm if you had troubles with insomnia then how did you fix it

I'm also a gymrat and lift 5×/week I'm not some neet who sits in a gooncave ok I just can't stop thinking at night or stay asleep even though I'm really tired