I have to get a lot of treatment done at the dentist but have a very bad fear and can't afford twilight sleep...what can i do?

Anxiolysis: Nearly every dentist has been trained in the use of pharmaceutical control of anxiety utilizing premedication with medications like benzodiazepines (valium, atavan, halcion, (triazolam) etc.). Talk to your dentist, then assess the reality of your needs, your concerns, and your desire to achieve/treat them. Good luck.

Dentistry: You may consider hospital dentistry under the national health plan. They may cover the anesthesia and all the work can be done at one time in hospital. There are dentist who specialize in hospital dentistry so check this option out. You may also want to see a therapist also under the national health plan if it is a benefit (i think it is) to get over the fear.