Another trainer NOW.
I've given riding lessons, and I never ever wanted a rider to come off, AND had the sense to look and see if rider was secure or not too.
That you have fallen as often as you have? Tells me your seat is not secure, your balance is not good, and that your trainer is not helping you in these issues. And if you are without balance? You should still be only working at walk, and on lunge most of that time.
To continue to push you, and to make you more fearful, is wrong, flat out wrong.
I will qualify this to say, and understand I am not accusing you of this, but it is something that needs to be said, especially for those who come to this thread because they have some of same issues.
IF you have pushed trainer to move you too fast, because you resented being kept at baby steps, and you have been given exercises to do to improve your balance, or suggestions have been made as to weight, balance, seat or what have you and have refused to do those things? This is what happens too often. Rider comes off.
Again, NOT saying you have done that. Just important to understand that trainers can get overruled by rider who pushes, as well as, which is what I feel is going on here, trainer pushes too hard.
And not sure what style you ride either?
Horses make me a better person.