Many parents use the "old fashion techniques" to educate their kids; techniques handed down to them by their own parents. Some of said techniques -the mos harmful in MHO- are a) pushing the kid to excel by remarking his / her mistake and comparing the kid's mistakes to their siblings' achievements. They believe the shame will change the kid behavior to what the parents think is correct. b) To publicly humiliate the kids (neighbors / friends); the idea is "He/she -to avoid embarrassment, will not make more mistakes."
These are only two of many...and the results are ferocious.

Parent's criticism gets internalised and is a huge problem.

If my experience is anything to go by, with parents like that you will suffer a life of self blame for every little error.

My situation is similar. Parents think they are doing so much for you but it was because they screwed up your mind / career path so badly and put in too little when it was needed that you have not attained financial independence.

My dad said that I was going to have to learn to 'stand on my own two feet'

which was a very patronising version of saying 'earn more than 22,000 dollars a year'.

You need to escape your mother by any means necessary. She sounds super toxic and if you allow her to continue she'll suck the life out of you.
Some families have bad coping mechanisms that are passed down from generation to generation. You have a chance to break the cycle. Know that at some point you may have to address breaking the cycle yourself if you find yourself doing the same behavior to a loved one in the future.
But for now know you have a right to your boundaries, start building them by working on an escape plan, focus on one thing at a time.

Move out asap even if you have to live with a roommate. Use her negativity as energy to prove her wrong. Spend more time with positive people. If you like music, listen to what makes you happy. When she starts on her rants pop in the headphones.

That is negativity you do not need and should not allow to continue. Make a change. She is suffering, perhaps from her own failures. Be kind but firm and distance yourself from her.

Sometimes when you can't get what you need from the one you need it from, you have to set a boundary and find ways to give yourself what you need. Parents are not always what we need them to be for us. They were once children and may not have gotten what they needed from their parents/guardians and never learned how to give.

The good news...YOU get to chose what kind of person you would like to be.