You need lessons to focus on you. Private. I rode in a group for a while and it was fun with friends, but we all noticed that our instructor was giving more time and more 'goals' towards one in our group who leased a horse and rode him. It wasn't right, as our time learning was diminished. Instructors can be bias if they think you're simply a 'lesson customer' vs. a 'lesson customer who leases and 'seems' more serious. I can't stand that honestly because it comes down to a matter of finances and not skill. But in your case it seems like a skill "issue"? It's the same story. Bias instructor who should be encouraging both of you to be your best and work on what you need.
The fact that she made you dismount early for the others benefit when you paid for your time is particularly venomous to me. Actions speak louder than words- your trainer has priorities that do not suit you. Change your trainer or change your barn. You need someone to encourage you. If you're stuck with this trainer, try taking private lessons-- and see if her attitude is better. If she is showing little interest in you, and you feel stuck, I can assure you that it's going to be a downward spiral mentally and emotionally...You need time for you. If someone (trainer, friend, whoever) is showing little interest in your endeavors or improvement, and you paid for their services, that is not a healthy relationship and I advise you to be wary about sticking around if you do not have a tough-skin in the long term.
cantering on, into the familiar and unknown