I’m scared that my new position will be as bad or worse than the old one, the same drama, the same backstabbing and playing favorites. It would be really tiring to get out of the frying pan to get into the fire.

As with any job, there will be some things that are better than your current one and some things that are worse. It seems like you already opened up the "quitting" can of worms at your current job. Reversing course is not impossible, but it is atypical. I would probably follow through with quitting based on what you said about your manager's attitude, and it also seems like you don't really like the job.

Apply to a bunch of places, do a bunch of interviews and get some offers. If you don't like your next job you can always leave that one. I would encourage you to try to treat people right at each job. You do not want to leave a giant wake of burned bridges. Eventually, people you work with at job A will show up at job B, and if you've been an asshole, no one is going to want to work with you. Conversely, if you are pleasant to work with, people will even recommend you for a new job.

Look up friend, change is scary and it's OK to be nervous. Put in some work to find a new job, re-examine your life. If it feels better, stay, if not, quit. There are new jobs all the time, and if your work is valuable in any way and you have a good attitude, you'll never have trouble finding work.

Your reaction to the uncertainty that comes w/ quitting your job is normal. IMO that is the aspect to investigate and try to accept what is and what isn't within your control

People crave routine, and experiencing a lifestyle change can be really difficult for a lot of people. It's the same reason why domestic abuse victims don't leave their abusers, or why people stay in loveless marriages - in their minds, it's easier to bear with the abuse than to adapt to an unknown lifestyle.

But human emotion is short-sighted. It can only see imminent uncertainty and change. It's the role of your conscious mind to think further ahead and determine if you stand to benefit from the change. If you've got a job lined up that you think will suit you better, then trust your judgement

The only way to find out is to try, and it's always a risk going into the unknown; your apprehension is understandable.

But the only way to improve your situation is to change it, and it sounds like your current working situation is pretty bad. Try not to let the fear stop you from moving forwards.

Best of luck finding somethig better!

It's become clear that you and the manager are not compatible. It may or may not be a reflection on either of you, but it's definitely not a good fit either way.

The best way to resolve a bad fit like this is to separate the pieces. Since they are the manager, that typically leaves it to you as the employee.

This isn't even a bad thing, necessarily. Switching jobs brings uncertainty and fear, but also opportunity. Not only do you have a chance to get into a situation more to your liking, you can branch out into new areas. These jumps also usually bring a pay bump, although that depends on how patient you can be and how hard you can negotiate.

There's a quote that has stuck with me for a while, and I encourage you to take it to heart.

"All of the best things in life come when you're out of your comfort zone, and everything worth doing is scary at first"

You're scared of the unknown, and understandably so. But it also doesn't sound like you've even looked into it. I can promise you don't currently have the only job that would work for you. It's also very unlikely that you have the best one. You probably don't even have the best one you could have by Xmas.

Go explore. The future is rosier than you think, if only you let it happen.

I'm scared that my new position will be as bad or worse

It will be. But it'll be a different kind of 'as bad' that you can maybe cope better with and maybe be content or happy. And, I worry you've shat in this bed already so you've got a best-before date.