Wiktionary
vb. 1 To leave secretly with another person. Usually with the intention of getting married or of living together against the wishes of the family. 2 To be misled by imagining that one's desires can come true.
Usage examples of "run away with".
But I don't think she ought to have run away with Baedeker that morning in Santa Croce.
There was no evidence of anything unusual the night before, and had we not ourselves heard the rapping noises, I should have felt that Louise's imagination had run away with her.
And Marion refused to run away with him and marry him, or to let him go to his father.
The first stretch was very steep and at present deserted, so they let their feet run away with them, leaning back for balance, footsteps drumming eerily in the shadows.
If one of the beasts tried, for whatever reason, to run away with the company's gear it wasn't going to get far.
As to Mademoiselle Catherine, who had also become full of thought, she allowed her reins to fall upon her courser's neck, without fearing that he would run away with her.
All this Sancho delivered with so much composure- wiping his nose from time to time- and with so little common-sense that his two hearers were again filled with wonder at the force of Don Quixote's madness that could run away with this poor man's reason.