[Miataracer]

its not the starter. the starter going bad would not cause the car to die. when you try to start it, does it crank? if so that is another way to rule out the starter.

any check engine codes?

have you checked for spark?

are you sure you are getting fuel? turn the key to the 'on' position in a very quiet place with the door open and listen for the fuel pump to prime the system. if it is working you will hear it