hedge that is frost, sea and wind resistant

Have been reading through other peoples questions. Our garden has also suffered. My escallonia suffered from a disease last year, I cut it back but I’m afraid this years frost has finished it. We have a boundary is 120 ft made up of olearia, not a leaf left on it. That hedge was planted with 19yrs. What are we to plant now, must we wait for years for it to grow as at this stage I can shake hands with the neighbours. What about Leylandii trees, can I top these every year to keep them a certain height.