I get tonsillitis maybe 1 or 2 times per years always get amoxicillin to cure it. How can I avoid this or other treatments ?

Tonsillectomy? You don't want to let throat infections go without treating them as bad things can result. If you're having that many infections each year, you might wanna consider having your tonsils removed. If you're an adult (as i assume) then this isn't a trivial operation but it might give you some relief.
Tonsillitis. Tonsillitis occuring only 1-2 times per year is best treated medically. Tonsillectomy is a major surgery that can be extremely painful and has a risk of severe bleeding. If tonsillitis occurs 3-4 times per year, then tonsillectomy is indicated. The american academy of otolaryngology follows this criteria.Also, tonsillectomy is indicated for treating serious disorders like sleep apnea.
Surgery. The only sure way to avoid getting tonsillitis is having them removed - tonsillectomy.