The idiom "fancy free" means doing something pleasantly or amusingly without any responsibility or obligation. It's often used to describe someone who is carefree and spontaneous, taking things as they come.

The idiom "that's the way the cookie crumbles" means that things happen as they are supposed to happen or as fate would have it. It suggests a sense of acceptance and resignation, indicating that there is no point in fighting against something that cannot be changed.

The idiom "head and shoulders above" means that someone or something is superior to others in a particular aspect, such as performance, quality, or appearance. It is often used to describe someone who stands out from the crowd or who is clearly better than others in a given situation.

The idiom "keep at arm's length" means to maintain a distance or avoid close contact or intimacy. It can also mean to treat someone with caution or skepticism, or to keep a professional or formal relationship.

The idiom "lose your marbles" means to lose one's sanity, composure, or control over a situation. It is often used to describe someone who is behaving erratically or has become unhinged.