Mrs. Jones plays a unique role among Alex's MI6 handlers. While Mr. Blunt is all-business, we get brief glimpses of a softer side to Mrs. Jones.
Don't get this twisted, though—Mrs. Jones is one straight-faced lady. She's right there alongside Mr. Blunt the entire time, happily sending Alex into terrifying situations. But we occasionally see the cracks in her armor, small indications that her work weighs heavier than she wants us to believe.
There's her habit of chewing peppermint, making Alex believe that the burden of sending countless men to their deaths is lighter "if her breath was sweet" (6.83). Furthermore, Alex notices a picture on her desk and finds himself "wondering if she was herself a mother" (6.68).
This might be wishful thinking on Alex's part—he never knew his mother and could certainly use one now—but the razor-thin glimpses we get into Mrs. Jones's heart reveal her to be a bit more empathetic than her, well, blunt counterpart.