Option 1 -> "run away to" means to escape to a specific place, which doesn't fit this context.
Option 2 -> "run away with" is an idiom meaning to let something control you beyond reason or get carried away.
Option 3 -> "run away from" means to escape or avoid something, but feelings cannot run away from you.
Option 4 -> "run away into" is not a standard phrasal verb and doesn't create meaningful sense here.
Hence, Option 2: run away with -> The phrase "let your feelings run away with you" is an idiomatic expression meaning to allow your emotions to control you or overwhelm your judgment, causing you to act irrationally -> correct