After 17 yrs in a vegetative state,have you the right to die with dignity and without Catholic interference?

Yes she should be. If she is unable to make that decision then her family must make one which should be respected by all and the church should out. To withdraw food and fluids is cruel though and they will have to administer some sort of pain relief. She will die because of dehydration within 3-5 days and not by starvation as her kidneys will fail.