My heart breaks for young you.
I think of when my DD started uni... she has a chronic (nothing too serious) condition and we agreed that if at any point she was ill I'd pick her up at the drop of a hat. I couldn't bear to think of her suffering and upset so far from home. Charging you rent when you were at college - I'm amazed! (also that a pp thinks this is OK!). You were a child still - as your parents it was their job to house you and feed you. If they'd still lived at 'home' surely they wouldn't have charged you to llive at home whilst under 18 and at college??
As loving parents (and you are clearly one) we want to help, support and encourage our children. The tricky years as parents, IME, is late teens in to early adulthood, when you feel as protective as ever, and love them as much as ever, but they are facing real adult problems and dilemmas. Being there for them if they need you is so important in those years, when they are becoming independent but need to know mum / dad / home is there when they need it.
Your parents put you at risk of being exploited by someone unscrupulous (leaving a young woman with not enough money to get by, living alone).
Your parents idea of parenting was very unusual and I would agree with others, negligent. I'm so pleased that you have built a lovely family around you, that you had lovely GPs, that you are still close to your brother and talk to him. Hats off to you.
But you don't have to pretend to them that it's OK. Don't let them tell you you were sensitive or difficult, or in any to blame for what they did. They were in the wrong 100%.