Unlike her father, Betty continued to believe in Bruce after he became a fugitive, and after he came back into her life years later, she helped him stay hidden from the U.S. military and track down Samuel Sterns.
In this continuity, Betty helped Bruce Banner with the Gamma Pulse experiment, which was part of the Bio-Tech Force Enhancement Project, an attempt to recreate the Super-Soldier Serum.
Following the battle with Abomination, Bruce went on the run again, and the last shot of Betty was her reminiscing on her brief reunion with him.
Betty Ross has been one of the Hulk key supporting characters since the Green (well, gray at first) Goliath’s comic book debut, so it was only appropriate that she was included in The Incredible Hulk, the second MCU film out of the gate.