Is Iron Man 3 the end of the road?

Picking up where The Avengers left off, Iron Man 3 finds Tony Stark in the clutches of post-traumatic stress from which he is often physically, emotionally debilitated.  Pepper Potts has moved into Tony’s Malibu mansion and it’s clear Tony is struggling in the aftermath of the events that took place in New York.  But, when a new threat arises in the