Oh! That is not a problem really! Lots of people with this allergy can have a nice holiday here!
Just avoid Padthai and Massamun curry, and some Tom-yum noodles: these have peanut added to the dishes.
But you could still have Padthai without peanut too; just tell the cook.
Chinese, Japanese and typical Thai food would be okay!
Some local Thais are also allergic to peanuts and all kinds of seafood too!!