What’s it like being able to just fall asleep?

I’ve always had issues falling asleep, even since I was a baby. I’ve taken melatonin for years, and if I’m not absolutely exhausted at the end of the day from work/working out, I just don’t get tired enough to fall asleep. My partner also has ADHD, but she’s able to knock out as soon as her head hits the pillow. What’s that like? I’m so jealous 😂