I need help developing a better relationship with bed/my sleep

TL;DR give me methods to get out of bed please!

Excuse the awful metaphor, but my bed is like a toxic ex.

I know it's bad to keep going back to yet I always fall back in the bad cycle. I feel better leaving and getting on with shit but my brain convinces me not to every time.

My horrible routine is as follows.

On a day if school, if I bother to get up, I am supposed to get up at 6 and be ready by 7. Most days I don't get up until 6:30-6:45 then I have to frantically get ready. This has led to a number of argument between my mother and I for being late. Then I'll be back in bed 10-12 and the cycle repeats.

On a day off, I'll barely get out of bed. I'll sleep till 11-12, stay in bed till 2-3, finally get up and get on with my day when I have to go to the bathroom. Then at some point I'll go to bed, anywhere between 9pm to 3am usually.

On top of that I regularly suffer from extreme nightmares, seeming so real that I struggle to sleep afterwards (often too scared to sleep the next night and stay up way too late) which through me off for most of the day. Particularly with the stress build up from school, these nightmares can happen 3-5 times a week. Sometimes I have bouts where they're nightly.

Rarely, I also have acute insomnia. I physically can't sleep for days to the point where I can't focus on anything, laze around in bed a majority of the day and am highly upset until I finally pass out.

With all this context, I'm hoping some could recommend ways to help me beat the battle with my bed.

I've tried jumping straight out of bed, but I always sleep through my alarms.

I've tried drinking lots of water before bed but most of the time I end up not being able to fall asleep or getting up late at night/early morning to go to the bathroom.

If anyone has even a small suggestion, I'd be more than grateful to hear it.