I'm so tired of being literally tired all the time.

Ok just want to mention I gave really bad insomnia, I take meds for it but I've been on them so long that my body is use to them so they kinda don't work. My doctor and I have tried to switch 4 different times to other meds but nothings working. At this point I'm so tired everyday even if I caught like 3 hours of sleep or even 8 hours. But it always rolls back to I'm tired all day, I wanna sleep but my body won't let me and the off chance I pass out for ME it's a 50 50 chance I either wake up feeling kinda rested or in a bad mood irritated. Now matter how what happens i always go back to being tired to the point of like saying I seriously wanna just die cuz I'm so over being sleepy. I will add the I drink coffee and energy to stay not so irritated even though I feel tired it's just not as bad. Yes I know caffeine is bad, I have an anxiety disorder so I know. I have quit both coffee and energy drinks for years but the tiredness NEVER goes away. I even one time slept 12 hours straight and later was still tired. I will admit I don't exercise. I was thinking of getting a bike and doing thar everyday. Do yall think mee being more active will help this issues? Please I need advice I'm miserable.