If you are eighteen, then you are an adult by law and should be free to make your own choices.
Your mother is behaving in a very tyrannical, selfish way and has not got the right to know where you are applying to go to University.
If you are still under eighteen, you are still a child though not for long, but regardless of how old you are, you need help in getting free of an abusive parent, help you should be able to get from the University itself, as many Universities offer counselling services - I used one such service myself and found a place to stay, for a while, before leaving the country. You should contact your Dad, plus 2 key University services (1 Counselling and 2, Finances) and explain your situation. Good luck!