Will/Are

The only difference is the word "ever".

Without the "ever", there would have been no difference in meaning between:
1. Will you let go of her?
2. Are you going to let go of her?

With the "ever", there would have been no difference in meaning between:
1. Will you ever let go of her?
2. Are you ever going to let go of her?

But the "ever" itself does make a difference.

Rommie

This is a difference, but it's very, very subtle.

maj made things less clear by turning the words around to make questions, but as simple statements, "You will" and "You are going to" are completely interchangable. As questions, those phrases become "Will you" and "Are you going to". This is also true in the third person.

The subtle difference occurs only in the first person - I and we. It is this:

Compare these sentences.

1. I am going to fight.
2. I shall fight.
3. I will fight

In theory, (1) and (2) - NOT (1) and (3) - are completely equivalent, but (3) is an emphatic form. In the first person, don't say WILL unless you REALLY MEAN IT. Remember, this is only so in the first person.

(In the second and third person, use "will" for normal and "shall" for emphasis).

This distinction is not used much these days, particularly not in America.

Rommie.

I think there is a difference in tone.

Will you ever let go of her? Is almost pleading; dramatic and femimine

Are you going to let go of her? Is abrupt; the tone is harsher.

If either sentence is written as part of a longer work, then the choice should be matched with the character asking the question.

Thank you pedant, I really think your explanation is very enlightening. How would you answer these questions, though?