i will never be able to get Sky reception (my house is surrounded by trees) an
guess from your message that you don't want to be chopping down the trees, so I can think of a few possibilities, but I need to know your postcode to be sure.
1. Reception from a distant Freeview transmitter using a Class I aerial mounted on a long pole;
2. A Freesat (or fSfS) system with a dish on a long pole (ie, find a better installer)
3. Go with a cable company until digital switchover.